Hydrogen Production System

ABSTRACT

A hydrogen production system comprising: a fuel source; a water source; and a hydrogen producer; where the fuel source and the water source are in fluid communication with the hydrogen producer; and where fuel enters the hydrogen producer from the fuel source and water enters the hydrogen producer from the water source and the fuel and the water do not come in contact with each other in the hydrogen producer.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part application of U.S. patentapplication Ser. Nos. 16/707,046, 16/707,066 and 16/707,084, filed Dec.9, 2019, which are continuation-in-part applications of U.S. patentapplication Ser. Nos. 16/699,453 and 16/699,461 filed Nov. 29, 2019,which are continuation-in-part applications of U.S. patent applicationSer. Nos. 16/693,268, 16/693,269, 16/693,270, and 16/693,271, filed Nov.23, 2019, which are continuation-in-part applications of U.S. patentapplication Ser. Nos. 16/684,838 and 16/684,864 filed Nov. 15, 2019,which are continuation-in-part applications of U.S. patent applicationSer. No. 16/680,770 filed Nov. 12, 2019, which is a continuation-in-partapplication of U.S. patent application Ser. Nos. 16/674,580, 16/674,629,16/674,657, 16/674,695 all filed Nov. 5, 2019, each of which claims thebenefit under 35 U.S.C. 119(e) of U.S. Provisional Patent ApplicationNo. 62/756,257 filed Nov. 6, 2018, U.S. Provisional Patent ApplicationNo. 62/756,264 filed Nov. 6, 2018, U.S. Provisional Patent ApplicationNo. 62/757,751 filed Nov. 8, 2018, U.S. Provisional Patent ApplicationNo. 62/758,778 filed Nov. 12, 2018, U.S. Provisional Patent ApplicationNo. 62/767,413 filed Nov. 14, 2018, U.S. Provisional Patent ApplicationNo. 62/768,864 filed Nov. 17, 2018, U.S. Provisional Patent ApplicationNo. 62/771,045 filed Nov. 24, 2018, U.S. Provisional Patent ApplicationNo. 62/773,071 filed Nov. 29, 2018, U.S. Provisional Patent ApplicationNo. 62/773,912 filed Nov. 30, 2018, U.S. Provisional Patent ApplicationNo. 62/777,273 filed Dec. 10, 2018, U.S. Provisional Patent ApplicationNo. 62/777,338 filed Dec. 10, 2018, U.S. Provisional Patent ApplicationNo. 62/779,005 filed Dec. 13, 2018, U.S. Provisional Patent ApplicationNo. 62/780,211 filed Dec. 15, 2018, U.S. Provisional Patent ApplicationNo. 62/783,192 filed Dec. 20, 2018, U.S. Provisional Patent ApplicationNo. 62/784,472 filed Dec. 23, 2018, U.S. Provisional Patent ApplicationNo. 62/786,341 filed Dec. 29, 2018, U.S. Provisional Patent ApplicationNo. 62/791,629 filed Jan. 11, 2019, U.S. Provisional Patent ApplicationNo. 62/797,572 filed Jan. 28, 2019, U.S. Provisional Patent ApplicationNo. 62/798,344 filed Jan. 29, 2019, U.S. Provisional Patent ApplicationNo. 62/804,115 filed Feb. 11, 2019, U.S. Provisional Patent ApplicationNo. 62/805,250 filed Feb. 13, 2019, U.S. Provisional Patent ApplicationNo. 62/808,644 filed Feb. 21, 2019, U.S. Provisional Patent ApplicationNo. 62/809,602 filed Feb. 23, 2019, U.S. Provisional Patent ApplicationNo. 62/814,695 filed Mar. 6, 2019, U.S. Provisional Patent ApplicationNo. 62/819,374 filed Mar. 15, 2019, U.S. Provisional Patent ApplicationNo. 62/819,289 filed Mar. 15, 2019, U.S. Provisional Patent ApplicationNo. 62/824,229 filed Mar. 26, 2019, U.S. Provisional Patent ApplicationNo. 62/825,576 filed Mar. 28, 2019, U.S. Provisional Patent ApplicationNo. 62/827,800 filed Apr. 1, 2019, U.S. Provisional Patent ApplicationNo. 62/834,531 filed Apr. 16, 2019, U.S. Provisional Patent ApplicationNo. 62/837,089 filed Apr. 22, 2019, U.S. Provisional Patent ApplicationNo. 62/840, 381 filed Apr. 29, 2019, U.S. Provisional Patent ApplicationNo. 62/844,125 filed May 7, 2019, U.S. Provisional Patent ApplicationNo. 62/844,127 filed May 7, 2019, U.S. Provisional Patent ApplicationNo. 62/847,472 filed May 14, 2019, U.S. Provisional Patent ApplicationNo. 62/849,269 filed May 17, 2019, U.S. Provisional Patent ApplicationNo. 62/852,045 filed May 23, 2019, U.S. Provisional Patent ApplicationNo. 62/856,736 filed Jun. 3, 2019, U.S. Provisional Patent ApplicationNo. 62/863,390 filed Jun. 19, 2019, U.S. Provisional Patent ApplicationNo. 62/864,492 filed Jun. 20, 2019, U.S. Provisional Patent ApplicationNo. 62/866,758 filed Jun. 26, 2019, U.S. Provisional Patent ApplicationNo. 62/869,322 filed Jul. 1, 2019, U.S. Provisional Patent ApplicationNo. 62/875,437 filed Jul, 17, 2019, U.S. Provisional Patent ApplicationNo. 62/877, 699 filed Jul. 23, 2019, U.S. Provisional Patent ApplicationNo. 62/888,319 filed Aug. 16, 2019, U.S. Provisional Patent ApplicationNo. 62/895,416 filed Sep. 3, 2019, U.S. Provisional Patent ApplicationNo. 62/896,466 filed Sep. 5, 2019, U.S. Provisional Patent ApplicationNo. 62/899,087 filed Sep. 11, 2019, U.S. Provisional Patent ApplicationNo. 62/904,683 filed Sep. 24, 2019, U.S. Provisional Patent ApplicationNo. 62/912,626 filed Oct. 8, 2019, U.S. Provisional Patent ApplicationNo. 62/925,210 filed Oct. 23, 2019, U.S. Provisional Patent ApplicationNo. 62/927,627 filed Oct. 29, 2019, U.S. Provisional Patent ApplicationNo. 62/928,326 filed Oct. 30, 2019, U.S. Provisional Patent ApplicationNo. 62/934,808 filed Nov. 13, 2019, U.S. Provisional Patent ApplicationNo. 62/939, 531 filed Nov. 22, 2019, U.S. Provisional Patent ApplicationNo. 62/941,358 filed Nov. 27, 2019, U.S. Provisional Patent ApplicationNo. 62/944,259 filed Dec. 5, 2019, U.S. Provisional Patent ApplicationNo. 62/944,756 filed Dec. 6, 2019, U.S. Provisional Patent ApplicationNo. 62/948,759 filed Dec. 16, 2019, and U.S. Provisional PatentApplication No. 62/955,443 filed Dec. 31, 2019. The entire disclosuresof each of these listed applications are hereby incorporated herein byreference.

TECHNICAL FIELD

This invention generally relates to electrochemical reactors. Morespecifically, this invention relates to electrochemical reactors toproduce syngas and hydrogen.

BACKGROUND

Syngas (i.e., synthesis gas) is a mixture consisting primarily ofhydrogen, carbon monoxide, and often carbon dioxide. It is used asintermediates to produce various products, such as synthetic naturalgas, ammonia, methanol, hydrogen, synthetic fuels, synthetic lubricants.Syngas may be produced from almost any hydrocarbon feedstock, such asnatural gas, coal, biomass, via steam reforming, dry reforming, partialoxidation, or gasification. Syngas is combustible and is often used ininternal combustion engines or for electricity generation although itsenergy density is less than half of natural gas.

Hydrogen in large quantities is needed in the petroleum and chemicalindustries. For example, large amounts of hydrogen are used in upgradingfossil fuels and in the production of ammonia or methanol orhydrochloric acid. Petrochemical plants need hydrogen for hydrocracking,hydrodesulfurization, hydrodealkylation. Hydrogenation processes toincrease the level of saturation of unsaturated fats and oils also needhydrogen. Hydrogen is also a reducing agent of metallic ores. Hydrogenmay be produced from electrolysis of water, steam reforming, lab-scalemetal-acid process, thermochemical methods, or anaerobic corrosion. Manycountries are aiming at a hydrogen economy.

Clearly, there is continuing need and interest to develop methods andsystems to produce these important gases.

SUMMARY

Further aspects and embodiments are provided in the following drawings,detailed description and claims. Unless specified otherwise, thefeatures as described herein are combinable and all such combinationsare within the scope of this disclosure.

One aspect of the present invention is a hydrogen production system thatincludes a fuel source, a water source, and a hydrogen producer. Thefuel source and the water source are in fluid communication with thehydrogen producer. The fuel enters the hydrogen producer from the fuelsource and water enters the hydrogen producer from the water source. Thefuel and the water do not come in contact with each other in thehydrogen producer.

In another aspect, the hydrogen producer includes a first electrode, asecond electrode, and an electrolyte between the first and secondelectrodes. The fuel source is in fluid communication with the firstelectrode and the water source is in fluid communication with the secondelectrode.

In still another aspect, the electrolyte includes doped ceria or wherethe electrolyte includes lanthanum chromite or a conductive metal orcombination thereof and a material selected from the group consisting ofdoped ceria, YSZ, LSGM, SSZ, and combinations thereof. The lanthanumchromite can include undoped lanthanum chromite, strontium dopedlanthanum chromite, iron doped lanthanum chromite, lanthanum calciumchromite, or combinations thereof. The conductive metal comprises Ni,Cu, Ag, Au, or combinations thereof.

In a still further aspect, the first electrode and the second electrodeinclude Ni or NiO and a material selected from the group consisting ofYSZ, CGO, SDC, SSZ, LSGM, and combinations thereof.

In a yet still further aspect, the first electrode includes doped orundoped ceria and a material selected from the group consisting of Cu,CuO, Cu₂O, Ag, Ag₂O, Au, Au₂O, Au₂O₃, Pt, Pd, Ru, Rh, stainless steel,and combinations thereof. The second electrode includes Ni or NiO and amaterial selected from the group consisting of YSZ, CGO, SDC, SSZ, LSGM,and combinations thereof.

In still yet another aspect of the invention, the fuel from the fuelsource provides heat for the hydrogen producer and the hydrogen producerhas no additional heat source.

In another aspect of the present invention, the hydrogen productionsystem further includes an oxidant source and a boiler, where the boileris in fluid communication with the oxidant source, the water source, andthe hydrogen producer.

In still another aspect, the boiler is in thermal communication with thehydrogen producer, the fuel entering into the hydrogen producer, theoxidant, the water, or combinations thereof.

In a still further aspect, the boiler is configured to receive exhaustfrom the first electrode of the hydrogen producer and to feed steam intothe second electrode of the hydrogen producer.

In a yet still further aspect, the fuel is partially oxidized in thehydrogen producer and further oxidized in the boiler.

In still yet another aspect of the invention, the hydrogen productionsystem further includes a steam turbine disposed between the boiler andthe hydrogen producer and in fluid communication with the boiler and thehydrogen producer.

In another aspect of the present invention, the hydrogen productionsystem further includes a steam reformer or an autothermal reformerdisposed between the fuel source and the hydrogen producer and in fluidcommunication with the fuel source and the hydrogen producer.

In still another aspect of the present invention, the hydrogenproduction system further includes a condenser configured to receiveexhaust from the second electrode of the hydrogen producer and torecycle water to the boiler and to output hydrogen.

In a still further aspect, the condenser is in thermal communicationwith the fuel.

In a yet still further aspect of the present invention, the hydrogenproduction system further includes a desulfurization unit disposedbetween the fuel source and the hydrogen producer and in fluidcommunication with the fuel source and the hydrogen producer.

In still yet another aspect, the hydrogen producer is configured to havea fuel inlet temperature no greater than 1000° C.

In another aspect of the present invention, the hydrogen producer isconfigured to have a fuel outlet temperature no less than 600° C.

In still another aspect, the hydrogen producer comprises nointerconnect.

In still yet another aspect of the present invention, a hydrogenproduction system is in fluid communication with a downstream unitconfigured to use hydrogen produced by the hydrogen producer in one ormore of process selected from the group consisting of: a Fischer-Tropsch(FT) reaction; a dry reforming reaction; a Sabatier reaction catalyzedby nickel; a Bosch reaction; a reverse water gas shift reaction; anelectrochemical reaction to produce electricity; production of ammonia;production of fertilizer; electrochemical compression of hydrogen forstorage or fueling a hydrogen vehicle; or a hydrogenation reaction.

BRIEF DESCRIPTION OF THE DRAWINGS

The following drawings are provided to illustrate certain embodimentsdescribed herein. The drawings are merely illustrative and are notintended to limit the scope of claimed inventions and are not intendedto show every potential feature or embodiment of the claimed inventions.The drawings are not necessarily drawn to scale; in some instances,certain elements of the drawing may be enlarged with respect to otherelements of the drawing for purposes of illustration.

FIG. 1A illustrates an electrochemical (EC) gas producer, according toan embodiment of this disclosure.

FIG. 1B illustrates an EC gas producer, according to an embodiment ofthis disclosure.

FIG. 2A illustrates a tubular EC gas producer, according to anembodiment of this disclosure.

FIG. 2B illustrates a cross section of a tubular EC gas producer,according to an embodiment of this disclosure.

FIG. 3A illustrates a cross section of a multi-tubular EC gas producer,according to an embodiment of the disclosure;

FIG. 3B illustrates a cross section of a multi-tubular EC gas producer,according to an embodiment of the disclosure;

FIG. 3C illustrates a cross section of a multi-tubular EC gas producer,according to an embodiment of the disclosure;

FIG. 3D illustrates a cross section of an EC gas producer, according toan embodiment of the disclosure;

FIG. 4A illustrates a portion of a method of manufacturing an EC gasproducer using a single point EMR source, according to an embodiment ofthe disclosure;

FIG. 4B illustrates a portion of a method of manufacturing an EC gasproducer using a ring-lamp EMR source, according to an embodiment of thedisclosure;

FIG. 4C illustrates a portion of a method of manufacturing an EC gasproducer using a single point EMR source, according to an embodiment ofthe disclosure;

FIG. 4D illustrates a portion of a method of manufacturing an EC gasproducer using a tubular EMR source, according to an embodiment of thedisclosure;

FIG. 5A illustrates a first step in a tape casting method to form atubular or multi-tubular EC gas producer, according to an embodiment ofthe disclosure;

FIG. 5B illustrates steps 2-4 in a tape casting method to form a tubularor multi-tubular EC gas producer, according to an embodiment of thedisclosure;

FIG. 6A, illustrates an example of a hydrogen production system 600 withno external heat source, according to an embodiment of the disclosure;

FIG. 6B illustrates an alternative hydrogen production system with noexternal heat source, according to an embodiment of the disclosure;

FIG. 7 illustrates a fuel cell component, according to an embodiment ofthe disclosure;

FIG. 8 schematically illustrates two fuel cells in a fuel cell stack,according to an embodiment of the disclosure;

FIG. 9A illustrates a perspective view of a fuel cell cartridge (FCC),according to an embodiment of the disclosure;

FIG. 9B illustrates a perspective view of a cross-section of a fuel cellcartridge (FCC), according to an embodiment of the disclosure;

FIG. 9C illustrates cross-sectional views of a fuel cell cartridge(FCC), according to an embodiment of the disclosure;

FIG. 9D illustrates top view and bottom view of a fuel cell cartridge(FCC), according to an embodiment of the disclosure;

FIG. 10A illustrates a cross-sectional view of a TFC, according to anembodiment of the disclosure;

FIG. 10B illustrates a cross-sectional view of a TFC, according to anembodiment of the disclosure;

FIG. 10C illustrates a cross-sectional view of a TFC, according to anembodiment of the disclosure;

FIG. 11A illustrates a cross-sectional view of a TFC comprising asupport, according to an embodiment of the disclosure;

FIG. 11B illustrates a cross-sectional view of a TFC comprising asupport, according to an embodiment of the disclosure;

FIG. 11C illustrates a cross-sectional view of a TFC comprising asupport, according to an embodiment of the disclosure;

FIG. 12A illustrates an impermeable interconnect 1202 with a fluiddispersing component 1204, according to an embodiment of the disclosure;

FIG. 12B illustrates an impermeable interconnect 1202 with two fluiddispersing components 1204, according to an embodiment of thedisclosure;

FIG. 12C illustrates segmented fluid dispersing components 1204 ofsimilar shapes but different sizes on an impermeable interconnect 1202,according to an embodiment of the disclosure;

FIG. 12D illustrates segmented fluid dispersing components 1204 ofsimilar shapes and similar sizes on an impermeable interconnect 1202,according to an embodiment of the disclosure;

FIG. 12E illustrates segmented fluid dispersing components 1204 ofsimilar shapes and similar sizes but closely packed on an impermeableinterconnect 1202, according to an embodiment of the disclosure;

FIG. 12F illustrates segmented fluid dispersing components 1204 ofdifferent shapes and different sizes on an impermeable interconnect1202, according to an embodiment of the disclosure;

FIG. 12G illustrates an impermeable interconnect 1202 and fluiddispersing component segment 1204, according to an embodiment of thedisclosure;

FIG. 12H illustrates an impermeable interconnect and fluid dispersingcomponent segment, according to an embodiment of the disclosure;

FIG. 12I illustrates an impermeable interconnect and fluid dispersingcomponent segments, according to an embodiment of the disclosure;

FIG. 12J illustrates an impermeable interconnect 1202 and a fluiddispersing component segment 1204, according to an embodiment of thedisclosure;

FIG. 12K illustrates a fluid dispersing component 1204, according to anembodiment of the disclosure;

FIG. 13A illustrates a template 1300 for making channeled electrodes,according to an embodiment of the disclosure;

FIG. 13B is a cross-sectional view of a half cell between a firstinterconnect and an electrolyte, according to an embodiment of thedisclosure;

FIG. 13C is a cross-sectional view of a half cell between a secondinterconnect and an electrolyte, according to an embodiment of thedisclosure;

FIG. 13D is a cross-sectional view of a half cell between a firstinterconnect and an electrolyte, according to an embodiment of thedisclosure;

FIG. 13E is a cross-sectional view of a half cell between a secondinterconnect and an electrolyte, according to an embodiment of thedisclosure;

FIG. 14A schematically illustrates segments of fluid dispersingcomponents in a first layer, according to an embodiment of thedisclosure;

FIG. 14B schematically illustrates fluid dispersing components in afirst layer along with a second layer, according to an embodiment of thedisclosure;

FIG. 14C schematically illustrates fluid dispersing components in afirst layer along with a second and third layer, according to anembodiment of the disclosure;

FIG. 14D schematically illustrates fluid dispersing components in afirst layer along with a second layer, according to an embodiment of thedisclosure;

FIG. 15 is an illustrative example of an electrode having dualporosities, according to an embodiment of the disclosure;

FIG. 16 illustrates a system for integrated deposition and heating usingelectromagnetic radiation (EMR), according to an embodiment of thedisclosure;

FIG. 17 is a scanning electron microscopy image; and

FIG. 18 schematically illustrates an example of a half cell in an ECreactor.

DETAILED DESCRIPTION Overview

Embodiments of methods, materials and processes described herein aredirected towards electrochemical reactors. Electrochemical reactorsinclude solid oxide fuel cells, solid oxide fuel cell stacks,electrochemical gas producers, electrochemical compressors, solid statebatteries, or solid oxide flow batteries.

Electrochemical gas producers can be used to produce syngas, hydrogen orother gasses for use as a fuel or feedstock for fuel cells, ammoniaproduction, fertilizer production, hydrogenation reactions, Boschreactions or other applications. The disclosure herein describes ahydrogen production system. Various components of the system aredescribed such as electrodes and electrolytes along with materials ofconstruction of the components. Other components described includecondensers, desulphurization units and boilers.

Definitions

The following description recites various aspects and embodiments of theinventions disclosed herein. No particular embodiment is intended todefine the scope of the invention. Rather, the embodiments providenon-limiting examples of various compositions and methods that areincluded within the scope of the claimed inventions. The description isto be read from the perspective of one of ordinary skill in the art.Therefore, information that is well-known to the ordinarily skilledartisan is not necessarily included.

The following terms and phrases have the meanings indicated below,unless otherwise provided herein. This disclosure may employ other termsand phrases not expressly defined herein. Such other terms and phrasesshall have the meanings that they would possess within the context ofthis disclosure to those of ordinary skill in the art. In someinstances, a term or phrase may be defined in the singular or plural. Insuch instances, it is understood that any term in the singular mayinclude its plural counterpart and vice versa, unless expresslyindicated to the contrary.

As used herein, the singular forms “a,” “an,” and “the” include pluralreferents unless the context clearly dictates otherwise. For example,reference to “a substituent” encompasses a single substituent as well astwo or more substituents, and the like. As used herein, “for example,”“for instance,” “such as,” or “including” are meant to introduceexamples that further clarify more general subject matter. Unlessotherwise expressly indicated, such examples are provided only as an aidfor understanding embodiments illustrated in the present disclosure andare not meant to be limiting in any fashion. Nor do these phrasesindicate any kind of preference for the disclosed embodiment.

As used herein, compositions and materials are used interchangeablyunless otherwise specified. Each composition/material may have multipleelements, phases, and components. Heating as used herein refers toactively adding energy to the compositions or materials.

The term “in situ” in this disclosure refers to the treatment (e.g.,heating) process being performed either at the same location or in thesame device of the forming process of the compositions or materials. Forexample, the deposition process and the heating process are performed inthe same device and at the same location, in other words, withoutchanging the device and without changing the location within the device.For example, the deposition process and the heating process areperformed in the same device at different locations, which is alsoconsidered in situ.

In this disclosure, a major face of an object is the face of the objectthat has a surface area larger than the average surface area of theobject, wherein the average surface area of the object is the totalsurface area of the object divided by the number of faces of the object.In some cases, a major face refers to a face of an item or object thathas a larger surface area than a minor face. In the case of planar fuelcells or non-SIS type fuel cells, a major face is the face or surface inthe lateral direction.

As used herein, lateral refers to the direction that is perpendicular tothe stacking direction of the layers in a non-SIS type fuel cell. Thus,lateral direction refers to the direction that is perpendicular to thestacking direction of the layers in a fuel cell or the stackingdirection of the slices to form an object during deposition. Lateralalso refers to the direction that is the spread of deposition process.

In this disclosure, a liquid precursor of a substance refers to adissolved form containing the substance, such as a salt in an aqueoussolution. For example, a copper salt dissolved in an aqueous solution isconsidered a liquid precursor of copper. Copper particlessuspended/dispersed (not dissolved) in a liquid are not consideredliquid precursors of copper.

As used herein, CGO refers to Gadolinium-Doped Ceria, also knownalternatively as gadolinia-doped ceria, gadolinium-doped cerium oxide,cerium(IV) oxide, gadolinium-doped, GDC, or GCO, (formula Gd:CeO₂). CGOand GDC are used interchangeably unless otherwise specified.

Syngas (i.e., synthesis gas) in this disclosure refers to a mixtureconsisting primarily of hydrogen, carbon monoxide and carbon dioxide.

In this disclosure, absorbance is a measure of the capacity of asubstance to absorb electromagnetic radiation (EMR) of a wavelength.Absorption of radiation refers to the energy absorbed by a substancewhen exposed to the radiation.

As used herein, ceria refers to cerium oxide, also known as ceric oxide,ceric dioxide, or cerium dioxide, is an oxide of the rare-earth metalcerium. Doped ceria refers to ceria doped with other elements, such assamaria-doped ceria (SDC), or gadolinium-doped ceria (GDC or CGO).

As used herein, chrorn to refers to chromium oxides, which includes allthe oxidation states of chromium oxides.

As used herein, “little to no water” refers to a water content nogreater than 1 g/m³ or no greater than 200 mg/m³ or no greater than 50mg/m³.

An interconnect in an electrochemical device (e.g., a fuel cell) isoften either metallic or ceramic that is placed between the individualcells or repeat units. Its purpose is to connect each cell or repeatunit so that electricity can be distributed or combined. An interconnectis also referred to as a bipolar plate in an electrochemical device. Aninterconnect being an impermeable layer as used herein refers to itbeing a layer that is impermeable to fluid flow. For example, animpermeable layer has a permeability of less than 1 micro darcy, or lessthan 1 nano darcy.

In this disclosure, an interconnect having no fluid dispersing elementrefers to an interconnect having no elements (e.g., channels) todisperse a fluid. A fluid may comprise a gas or a liquid or a mixture ofa gas and a liquid. Such fluids may include one or more of hydrogen,methane, ethane, propane, butane, oxygen, ambient air or lighthydrocarbons (i.e., pentane, hexane, octane). Such an interconnect mayhave inlets and outlets (i.e., openings) for materials or fluids to passthrough.

In this disclosure, the term “microchannels” is used interchangeablywith microfluidic channels or microfluidic flow channels.

In this disclosure, sintering refers to a process to form a solid massof material by heat or pressure, or a combination thereof, withoutmelting the material to the extent of liquefaction. For example,material particles are coalesced into a solid or porous mass by beingheated, wherein atoms in the material particles diffuse across theboundaries of the particles, causing the particles to fuse together andform one solid piece. In this disclosure and the appended claims,T_(sinter) refers to the temperature at which this phenomenon begins totake place.

As used herein, the term “pore former” is intended to have a relativelybroad meaning. “Pore former” may be referring to any particulatematerial that is included in a composition during formation, which maypartially or completely vacate a space by a process, such as heating,combustion or vaporizing. As used herein, the term “electricallyconductive component” is intended to refer to components in a fuel cell,such as electrodes and interconnects, that are electrically conductive.

For illustrative purposes, the production of solid oxide fuel cells(SOFCs) will be used as an example system herein to describe the variousembodiments. As one in the art recognizes though, the methodologies andthe manufacturing processes described herein are applicable to anyelectrochemical device, reactor, vessel, catalyst, etc. Examples ofelectrochemical devices or reactors includes electrochemical (EC) gasproducer electrochemical (EC) compressor, solid oxide fuel cells, solidoxide fuel cell stack, solid state battery, or solid oxide flow battery.In an embodiment, an electrochemical reactor comprises solid oxide fuelcell, solid oxide fuel cell stack, electrochemical gas producer,electrochemical compressor, solid state battery, or solid oxide flowbattery. Catalysts include Fischer Tropsch (FT) catalysts or reformercatalysts. Reactor/vessel includes FT reactor or heat exchanger.

Electrochemical (EC) Gas Producer

FIG. 1A illustrates an electrochemical (EC) gas producer 100, accordingto an embodiment of this disclosure. EC gas producer device 100comprises first electrode 101, electrolyte 103 a second electrode 102.First electrode 101 is configured to receive a fuel and no oxygen 104.Second electrode 102 is configured to receive water or nothing asdenoted by arrow 105. Device 100 is configured to simultaneously producehydrogen 107 from second electrode 102 and syngas 106 from firstelectrode 101. In an embodiment, 104 represents methane and water ormethane and carbon dioxide entering device 100. In other embodiments,103 represents an oxide ion conducting membrane. In an embodiment, firstelectrode 101 and second electrode 102 may comprise Ni-YSZ or NiO-YSZ.Arrow 104 represents an influx of hydrocarbon and water or hydrocarbonand carbon dioxide. Arrow 105 represents an influx of water or water andhydrogen. In some embodiments, electrode 101 comprises Cu-CGO furtheroptionally comprising CuO or Cu₂O or combinations thereof. Electrode 102comprises Ni-YSZ or NiO-YSZ. Arrow 104 represents an influx ofhydrocarbon with little to no water, with no carbon dioxide, and with nooxygen, and 105 represents an influx of water or water and hydrogen.Since water provides the oxide ion (which is transported through theelectrolyte) needed to oxidize the hydrocarbon/fuel at the oppositeelectrode, water is considered the oxidant in this scenario.

FIG. 1B illustrates an EC gas producer 110, according to an embodimentof this disclosure. EC gas producer device 110 comprises first electrode111, second electrode 112, and electrolyte 113 between the electrodes.The first electrode 111 is configured to receive a fuel and no oxygen104, wherein second electrode 112 is configured to receive water ornothing. In some embodiments, 113 represents a proton conductingmembrane, 111 and 112 represent Ni-barium zirconate electrodes. Hydrogen107 is produced from second electrode 112 and syngas 106 is producedfrom first electrode 111.

In this disclosure, no oxygen means there is no oxygen present at firstelectrode 101, 111 or at least not enough oxygen that would interferewith the reaction. Also, in this disclosure, water only means that theintended feedstock is water and does not exclude trace elements orinherent components in water. For example, water containing salts orions is considered to be within the scope of water only. Water only alsodoes not require 100% pure water but includes this embodiment. Inembodiments, the hydrogen produced from second electrode 102, 112 ispure hydrogen, which means that in the produced gas phase from thesecond electrode, hydrogen is the main component. In some cases, thehydrogen content is no less than 99.5%. In some cases, the hydrogencontent is no less than 99.9%. In some cases, the hydrogen produced fromthe second electrode is the same purity as that produced fromelectrolysis of water.

In an embodiment, first electrode 101, 111 is configured to receivemethane and water or methane and carbon dioxide. In an embodiment, thefuel comprises a hydrocarbon having a carbon number in the range of1-12, 1-10 or 1-8. Most preferably, the fuel is methane or natural gas,which is predominantly methane. In an embodiment, the device does notgenerate electricity. In an embodiment, the device comprises a mixerconfigured to receive at least a portion of the first electrode productand at least a portion of the second electrode product. The mixer may beconfigured to generate a gas stream in which the hydrogen to carbonoxides ratio is no less than 2, or no less than 3 or between 2 and 3.

In an embodiment, first electrode 101, 111 or second electrode 102, 112,or both the first electrode 101, 111 and second electrode 102, 112comprise a catalyst and a substrate, wherein the mass ratio between thecatalyst and the substrate is no less than 1/100, or no less than 1/10,or no less than 1/5, or no less than 1/3, or no less than 1/1. In anembodiment, the catalyst comprises nickel oxide, silver, cobalt, cesium,nickel, iron, manganese, nitrogen, tetra-nitrogen, molybdenum, copper,chromium, rhodium, ruthenium, palladium, osmium, iridium, or platinum,or combinations thereof. In an embodiment, the substrate comprisesgadolinium, CeO₂, ZrO₇, SiO₂, TiO₂, steel, cordierite(2MgO-2Al₂O₃-5SiO₂), aluminum titanate (Al₂TiO₅), silicon carbide (SEC),all phases of aluminum oxide, yttria or scandia-stabilized zirconia(YSZ), gadolinia or samaria-doped ceria, or combinations thereof. Insome embodiments, first electrode 101, 111 or second electrode 102, 112,or both the first electrode 101, 111 and second electrode 102, 112,comprise a promoter wherein the promoter is selected from the groupconsisting of Mo, W, Ba, K, Mg, Fe, and combinations thereof. In anembodiment, an anode (e.g., the first electrode or the second electrode)comprises a catalyst, wherein the catalyst is selected from the groupconsisting of nickel, iron, palladium, platinum, ruthenium, rhodium,cobalt, and combinations thereof.

In some embodiments, the electrodes and electrolyte form a repeat unit.A device may comprise two or more repeat units separated byinterconnects. In a preferred embodiment, the interconnects comprise nofluid dispersing element. In an embodiment, first electrode 101, 111 orsecond electrode 102, 112, or both the first electrode 101, 111 andsecond electrode 102, 112, comprise fluid channels. Alternatively, thefirst electrode 101, 111 or second electrode 102, 112, or both the firstelectrode 101, 111 and second electrode 102, 112, comprise fluiddispersing components.

Also discussed herein is an assembly method comprising forming a firstelectrode 101, 111, forming a second electrode 102, 112, and forming anelectrolyte 103, 113 between the electrodes, wherein the electrodes andelectrolyte are assembled as they are formed. Forming may comprisematerial jetting, binder jetting, inkjet printing, aerosol jetting, oraerosol jet printing, vat photopolymerization, powder bed fusion,material extrusion, directed energy deposition, sheet lamination,ultrasonic inkjet printing, or combinations thereof. The electrodes andelectrolyte may form a repeat unit. The method may further compriseforming two or more repeat units and forming interconnects between thetwo or more repeat units. The assembly method may further compriseforming fluid channels or fluid dispersing components in the firstelectrode 101, 111 or the second electrode 102, 112, or both the firstelectrode 101, 111 and second electrode 102, 112. The forming method maycomprise heating in situ. In a preferred embodiment, the heatingcomprises EMR. EMR may comprise one or more of UV light, nearultraviolet light, near infrared light, infrared light, visible light,laser or electron beam.

The first electrode 101, 111 is configured to receive a fuel and nooxygen, wherein the second electrode 102, 112 is configured to receivewater only or nothing, wherein the device is configured tosimultaneously produce hydrogen from the second electrode 102, 112 andsyngas from the first electrode 101, 111.

Further discussed herein is a method comprising providing a devicecomprising a first 101, 111 electrode, a second electrode 102, 112, andan electrolyte 103, 113 between the electrodes, introducing a fuelwithout oxygen to the first electrode 101, 111, introducing water onlyor nothing to the second electrode 102, 112 to generate hydrogen,extracting hydrogen from the second electrode 102, 112, and extractingsyngas from the first electrode 101, 111. In preferred embodiments, thefuel comprises methane and water or methane and carbon dioxide. Inpreferred embodiments, the fuel comprises a hydrocarbon having a carbonnumber in the range of 1-12 or 1-10 or 1-8.

In an embodiment, the method comprises feeding at least a portion of theextracted syngas to a Fischer-Tropsch reactor. In an embodiment, themethod comprises feeding at least a portion of the extracted hydrogen tothe Fischer-Tropsch reactor. In an embodiment, the at least portion ofthe extracted syngas and the at least portion of the extracted hydrogenare adjusted such that the hydrogen to carbon oxides ratio is no lessthan 2, or no less than 3, or between 2 and 3.

In an embodiment, the fuel is directly introduced into the firstelectrode 101, 111 or water is directly introduced into the secondelectrode 102, 112, or both the first electrode 101, 111 and secondelectrode 102, 112. In an embodiment, the first electrode 101, 111 orsecond electrode 102, 112, or both the first electrode 101, 111 andsecond electrode 102, 112, comprise a catalyst and a substrate, whereinthe mass ratio between the catalyst and the substrate is in no less than1/100, or no less than 1/10, or no less than 1/5, or no less than 1/3,or no less than 1/1. In preferred embodiments, the catalyst comprisesnickel oxide, silver, cobalt, cesium, nickel, iron, manganese, nitrogen,tetra-nitrogen, molybdenum, copper, chromium, rhodium, ruthenium,palladium, osmium, iridium, platinum, or combinations thereof. Inpreferred embodiments, the substrate comprises gadolinium, CeO₂, ZrO₂,SiO₂, TiO₂, steel, cordierite (2MgO-2Al₂O₃-5SiO₂), aluminum titanate(Al₂TiO₅), silicon carbide (SEC), all phases of aluminum oxide, yttriaor scandia-stabilized zirconia (YSZ), gadolinia or samaria-doped coria,or combinations thereof.

In an embodiment, the method comprises applying a potential differencebetween the first electrode 101, 111 and the second electrode 102, 112.In an embodiment, the method comprises using the extracted hydrogen inone of the following reactions, or combinations thereof: Fischer-Tropsch(FT) reaction, dry reforming reactions, Sabatier reaction catalyzed bynickel, Bosch reaction, reverse water gas shift reaction,electrochemical reaction to produce electricity, production of ammoniaand/or fertilizer, electrochemical compressor for hydrogen storage orfueling hydrogen vehicles, or hydrogenation reactions.

The gas producer is not a fuel cell and does not generate electricity,in various embodiments. Electricity may be applied to the gas producerat the anode and cathode in some cases. In other cases, electricity isnot needed.

Herein disclosed is a device comprising a first electrode, a secondelectrode, and an electrolyte between the electrodes, wherein the firstelectrode and the second electrode comprise a metallic phase that doesnot contain a platinum group metal when the device is in use, andwherein the electrolyte is oxide ion conducting. In an embodiment,wherein the first electrode comprises Ni or NiO and a material selectedfrom the group consisting of YSZ, CGO, samaria-doped ceria (SDC),scandia-stabilized zirconia (SSZ), LSGM, and combinations thereof. In anembodiment, the first electrode is configured to receive a fuel andwater or a fuel and carbon dioxide. In an embodiment, said fuelcomprises a hydrocarbon or hydrogen or carbon monoxide or combinationsthereof.

In an embodiment, the first electrode comprises doped or undoped ceriaand a material selected from the group consisting of Cu, CuO, Cu2O, Ag,Ag₂O, Au, Au₂O, Au₂O₃, stainless steel, and combinations thereof. In anembodiment, the first electrode is configured to receive a fuel withlittle to no water. In an embodiment, said fuel comprises a hydrocarbonor hydrogen or carbon monoxide or combinations thereof. In anembodiment, the second electrode comprises Ni or NiO and a materialselected from the group consisting of yttria-stabilized zirconia (YSZ),ceria gadolinium oxide (CGO), samaria-doped ceria (SDC),scandia-stabilized zirconia (SSZ), lanthanum strontium gallate magnesite(LSGM), and combinations thereof. In an embodiment, the second electrodeis configured to receive water and hydrogen and configured to reduce thewater to hydrogen. In an embodiment, the electrolyte comprises dopedceria or wherein the electrolyte comprises lanthanum chromite or aconductive metal or combination thereof and a material selected from thegroup consisting of doped ceria, YSZ, LSGM, SSZ, and combinationsthereof. In an embodiment, the lanthanum chromite comprises undopedlanthanum chromite, strontium doped lanthanum chromite, iron dopedlanthanum chromite, lanthanum calcium chromite, or combinations thereof.In an embodiment, the conductive metal comprises Ni, Cu, Ag, Au, orcombinations thereof.

In an embodiment, the first electrode 101, 111 or second electrode 102,112 or both the first electrode 101, 111 and second electrode 102, 112comprise fluid channels. Alternatively, the first electrode 101, 111 orsecond electrode 102, 112 or both the first electrode 101, 111 andsecond electrode 102, 112 comprise fluid dispersing components. In anembodiment, the electrodes and electrolyte 103, 113 form a repeat unitand wherein a device comprises multiple repeat units separated byinterconnects. In an embodiment, the interconnects comprise no fluiddispersing elements. In an embodiment, the electrodes 101, 102, 111, 112and electrolyte 103, 113 may be planar. Fluid dispersing components orfluid channels in the electrodes function to distribute fluids, e.g.,reactive gases (such as methane, hydrogen, carbon monoxide, air, oxygen,steam etc.), in an electrochemical reactor. As such, traditionalinterconnects with channels are no longer needed. The design andmanufacturing of such traditional interconnects with channels is complexand expensive. According to this disclosure, the interconnects aresimply impermeable layers that conduct or collect electrons, having nofluid dispersing elements.

In an embodiment, the device comprises no interconnect. In anembodiment, the electrolyte 103, 113 conducts oxide ions and electrons.In an embodiment, the electrodes 101, 102, 111, 112 and the electrolyte103, 113 are tubular. In some embodiments, the electrochemical reactionsat the anode and the cathode are spontaneous without the need to applypotential/electricity to the reactor. In such cases, the interconnect isno longer needed, which significantly simplifies the device. In suchcases, the electrolyte in the device conducts both oxide ions andelectrons.

In an embodiment, the device comprises a reformer upstream of the firstelectrode 101, 111, wherein the first electrode 101, 111 comprises Ni orNiO or a combination thereof. In an embodiment, the reformer is a steamreformer or an autothermal reformer. In an embodiment, the device isconfigured to operate at a temperature no less than 500° C., or no lessthan 600° C., or no less than 700° C.

In an embodiment, the electrodes and the electrolyte are tubular withthe first electrode being outermost and the second electrode beinginnermost, wherein the first electrode comprises doped or undoped ceriaand a material selected from the group consisting of Cu, CuO, Cu₂O, Ag,Ag₂O, Au, Au₂O, Au₂O₃, stainless steel, and combinations thereof. In anembodiment, the electrodes and the electrolyte are tubular with thefirst electrode being outermost and the second electrode beinginnermost, wherein the second electrode is configured to receive waterand hydrogen.

Herein also disclosed is a device comprising a first electrode, a secondelectrode, and an electrolyte between the electrodes, wherein the firstelectrode comprises doped lanthanum chromium oxide and doped or undopedceria, wherein the second electrode comprises Ni or NiO and a materialselected from the group consisting of YSZ, CGO, Samaria-doped ceria(SDC), Scandia-stabilized zirconia (SSZ), LSGM, ceria, and combinationsthereof, and wherein the electrolyte is oxide ion conducting. In anembodiment, the electrolyte comprises YSZ, CGO, LSGM, SSZ, SDC, ceria,or combinations thereof. In an embodiment, the device is planar. In anembodiment, the device is tubular.

Further discussed herein is a method of making a device, comprisingforming a first electrode, forming a second electrode, and forming anelectrolyte between the electrodes, wherein the first electrodecomprises doped lanthanum chromium oxide and doped or undoped ceria,wherein the second electrode comprises Ni or NiO and a material selectedfrom the group consisting of YSZ, CGO, Samaria-doped ceria (SDC),Scandia-stabilized zirconia (SSZ), LSGM, ceria, and combinationsthereof, and wherein the electrolyte is oxide ion conducting. In anembodiment, the electrolyte comprises YSZ, CGO, LSGM, SSZ, SDC, ceria,or combinations thereof. In an embodiment, said forming comprisesmaterial jetting, binder jetting, inkjet printing, aerosol jetting, oraerosol jet printing, vat photopolymerization, powder bed fusion,material extrusion, directed energy deposition, sheet lamination, orultrasonic inkjet printing, or combinations thereof. In an embodiment,the forming comprises extrusion, dip coating, spraying, spin coating,brush coating, pasting, or combinations thereof. In an embodiment, theforming comprises heating using an electromagnetic radiation source or afurnace.

Discussed herein is a method of making a device, comprising forming afirst electrode, forming a second electrode, and forming an electrolytebetween the electrodes, wherein the first electrode and the secondelectrode comprise a metallic phase that does not contain a platinumgroup metal when the device is in use, and wherein the electrolyte isoxide ion conducting. In an embodiment, the electrodes and electrolyteare assembled as they are formed. In an embodiment, said electrodes andelectrolyte form a repeat unit and said method comprises forming saidmultiple repeat units and forming interconnects between the repeatunits. In an embodiment, the interconnects comprise no fluid dispersingelement. In an embodiment, the method comprises forming fluid channelsor fluid dispersing components in the first electrode or the secondelectrode or both the first electrode and the second electrode.

In an embodiment, the first electrode comprises Ni or NiO and a materialselected from the group consisting of YSZ, CGO, samaria-doped ceria(SDC), scandia-stabilized zirconia (SSZ), LSGM, and combinationsthereof. In an embodiment, the first electrode comprises doped orundoped ceria and a material selected from the group consisting of Cu,CuO, Cu₂O, Ag, Ag₂O, Au, Au₂O, Au₂O₃, stainless steel, and combinationsthereof. In an embodiment, the second electrode comprises Ni or NiO anda material selected from the group consisting of YSZ, CGO, samaria-dopedceria (SDC), scandia-stabilized zirconia (SSZ), LSGM, cerin, andcombinations thereof. In an embodiment, the electrolyte comprises YSZ,CGO, LSGM, SSZ, SDC, ceria, or combinations thereof.

In an embodiment, the forming comprises material jetting, binderjetting, inkjet printing, aerosol jetting, aerosol jet printing, vatphotopolymerization, powder bed fusion, material extrusion, directedenergy deposition, sheet lamination, ultrasonic inkjet printing, orcombinations thereof. In an embodiment, the method comprises heating insitu. In an embodiment, the heating comprises electromagnetic radiation(EMR). In an embodiment, EMR comprises UV light, near ultraviolet light,near infrared light, infrared light, visible light, laser, electronbeam, or combinations thereof. In an embodiment, EMR is provided by axenon lamp. In an embodiment, the electrodes and the electrolyte areplanar. In an embodiment, the device comprises no interconnect. In anembodiment, the electrolyte conducts oxide ions and electrons.

In an embodiment, the forming comprises a) depositing a composition on asubstrate to form a slice; b) drying the slice using a non-contactdryer; c) heating the slice using electromagnetic radiation (EMR) orconduction or both. In an embodiment, the method comprises repeatingsteps a)-c) to produce the device slice by slice. In an embodiment, themethod comprises comprising d) measuring the slice temperature T withintime t after the last exposure of the EMR without contacting the slice,wherein t is no greater than 5 seconds, or no greater than 4 seconds, orno greater than 3 seconds, no greater than 2 seconds, or no greater than1 second. In an embodiment, the method comprises e) comparing T withT_(sinter), wherein T_(sinter) is no less than 45% of the melting pointof the composition if the composition is non-metallic; or whereinT_(sinter) is no less than 60% of the melting point of the compositionif the composition is metallic. In an embodiment, the method comprisese) comparing T with T_(sinter), wherein T_(sinter) is previouslydetermined by correlating the measured temperature with microstructureimages of the slice, scratch test of the slice, electrochemicalperformance test of the slice, dilatometry measurements of the slice,conductivity measurements of the slice, or combinations thereof. In anembodiment, the method comprises heating the slice using EMR orconduction or both in a second stage if T is less than 90% ofT_(sinter).

In an embodiment, drying takes place for a period in the range of nogreater than 5 minutes, or no greater than 3 minutes, or no greater than1 minute, or from 1 s to 30 s, or from 3 s to 10 s. In an embodiment,the non-contact dryer comprises infrared heater, hot air blower,ultraviolet light source, or combinations thereof.

As an example, all the layers of an EC gas producer are formed andassembled via printing. The materials for making the anode, cathode,electrolyte, and the interconnect, respectively, are made into an inkform comprising a solvent and particles (e.g., nanoparticles). The inkoptionally comprises a dispersant, binder, plasticizer, surfactant,co-solvent, or combinations thereof. For the anode and the cathode of agas producer, NiO and YSZ particles are mixed with a solvent, whereinthe solvent is water (e.g., de-ionized water) or an alcohol (e.g.,butanol) or a mixture of alcohols. Organic solvents other than alcoholsmay also be used. For the electrolyte, YSZ particles are mixed with asolvent, wherein the solvent is water (e.g., de-ionized water) or analcohol (e.g., butanol) or a mixture of alcohols. Organic solvents otherthan alcohols may also be used. For the interconnect, metallic particles(such as, silver nanoparticles) are dispersed or suspended in a solvent,wherein the solvent may include water (e.g., de-ionized water), organicsolvents (e.g., mono-, di-, or tri-ethylene glycols or higher ethyleneglycols, propylene glycol, 1,4-butanediol or ethers of such glycols,thiodiglycol, glycerol and ethers and esters thereof, polyglycerol,mono-, di-, and tri-ethanolamine, propanolamine, N,N-dimethylformamide,dimethyl sulfoxide, dimethylacetamide, N-methylpyrrolidone,1,3-dimethylimidazolidone, methanol, ethanol, isopropanol, n-propanol,diacetone alcohol, acetone, methyl ethyl ketone, propylene carbonate),and combinations thereof. For a barrier layer, CGO particles may bedissolved, dispersed or suspended in a solvent, wherein the solvent iswater (e.g., de-ionized water) or an alcohol (e.g., butanol) or amixture of alcohols. Organic solvents other than alcohols may also beused. CGO is used as barrier layer for LSCF. YSZ may also be used as abarrier layer for LSM.

Tubular and Multi-Tubular EC Gas Producers

FIG. 2A illustrates (not to scale) a tubular EC gas producer 200,according to an embodiment of this disclosure. Tubular EC gas producer200 includes an inner tubular structure 202, an outer tubular structure204, and an electrolyte 206 disposed between the inner and outer tubularstructures 202, 204, respectively. In some embodiments, electrolyte 206may instead comprise a membrane. Tubular gas producer 200 furtherincludes a void space 208 for fluid passage.

FIG. 2B illustrates (not to scale) a cross section of a tubular EC gasproducer 200, according to an embodiment of this disclosure. Tubular ECgas producer 200 includes a first inner tubular structure 202, a secondouter tubular structure 204, and an electrolyte 206 between the innerand outer tubular structures 202, 204. In some embodiments, electrolyte206 may be referred to as a membrane. Tubular gas producer 200 furtherincludes a void space 208 for fluid passage.

In an embodiment, inner tubular structure 202 comprises an electrode.Inner tubular structure 202 may be an anode or a cathode. In anembodiment, inner tubular structure 202 may be porous. Inner tubularstructure 202 may comprise Ni or NiO and a material selected from thegroup consisting of YSZ, CGO, samaria-doped ceria (SDC),scandia-stabilized zirconia (SSZ), LSGM, and combinations thereof. Innertubular structure 202 may comprise doped or undoped ceria and a materialselected from the group consisting of Cu, CuO, Cu₂O, Ag, Ag₂O, Au, Au₂O,Au₂O₃, stainless steel, and combinations thereof. In an embodiment,outer tubular structure 204 comprises an electrode. Outer tubularstructure 204 may be an anode or a cathode. Outer tubular structure 204may comprise Ni or NiO and a material selected from the group consistingof YSZ, CGO, samaria-doped ceria (SDC), scandia-stabilized zirconia(SSZ), LSGM, and combinations thereof. Outer tubular structure 204 maycomprise doped or undoped ceria and a material selected from the groupconsisting of Cu, CuO, Cu₂O, Ag, Ag₂O, Au, Au₂O, Au₂O₃, stainless steel,and combinations thereof. It should be noted that the listing ofmaterials above is not limiting.

In embodiments, electrolyte 206 comprises doped ceria or wherein theelectrolyte comprises lanthanum chromite or a conductive metal orcombination thereof and a material selected from the group consisting ofdoped ceria, YSZ, LSGM, SSZ, and combinations thereof. In an embodiment,the lanthanum chromite comprises undoped lanthanum chromite, strontiumdoped lanthanum chromite, iron doped lanthanum chromite, lanthanumcalcium chromite, or combinations thereof. In an embodiment, theconductive metal comprises Ni, Cu, Ag, Au, or combinations thereof.Electrolyte 206 is be oxide ion conducting. In some cases, electrolyte206 is both oxide ion and electronically conducting. In someembodiments, the producer 200 further comprises one or moreinterconnects.

FIG. 3A illustrates a cross section of a multi-tubular EC gas producer300, according to an embodiment of the disclosure. EC gas producer 300comprises an inner electrode 302, an outer electrode 304, and anelectrolyte 306 between the electrodes 302, 304. In some embodiments,electrolyte 306 is referred to as a membrane. The inner electrode 302comprises multiple tubular-like void spaces 308 joined in the radialdirection. Void spaces 308 allow for fluid passage. Void spaces 308 mayalso be referred to as fluid passages. The multi-tubular structure 300comprises multiple fluid passages 308 in the axial direction of thetubular structure 300. The cross-section of void spaces 308 may becircular-like, oval-like or other similar shapes. The cross-sections ofspaces 308 may be irregular shaped as illustrated in FIG. 3A. Producer300 has a cross section having a length and a width, wherein the lengthis at least 2 times the width and the cross section is orthogonal to theaxial direction of the tubular. Multi-tubular structure 300 is comprisedof multiple individual tubular structures 309 (denoted by a dottedline).

Inner electrode 302 in producer 300 may be of unitary construction andhas no brazed or soldered part. In an embodiment, the producer 300 is ofunitary construction and has no brazed or soldered part. In anembodiment, the electrolyte 306 is oxide ion conducting and is solidstate. In an embodiment, the electrolyte comprises a material previouslylisted herein for electrolyte 206 in tubular reactor 200. Inembodiments, the electrodes 302, 304 may comprise one or more materialspreviously listed herein for tubular structures 202, 204 in tubularreactor 200. In some embodiments, the producer 300 further comprises oneor more interconnects.

FIG. 3B illustrates a cross section of a multi-tubular EC gas producer320, according to an embodiment of the disclosure. Gas producer has arectangular-like shape cross-section. EC gas producer 320 comprises aninner electrode 302, an outer electrode 304, and an electrolyte 306between the electrodes 302, 304. In some embodiments, a membrane may beused in place of electrolyte 306. The inner electrode 302 comprisesmultiple void spaces 308 joined in the radial direction of thetubular-like void spaces 308. Void spaces 308 allow for fluid passage.The multiple tubular structure 320 comprises multiple fluid passages 308in the axial direction of the tubular structure 320. The cross-sectionof void spaces 308 may be circular-like, oval-like, square-like,hexagonal-like, triangular-like or other similar shapes in a random orregular fashion. Producer 320 has a cross section having a length and awidth, wherein the length is at least 2 times the width and the crosssection is orthogonal to the axial direction of the tubular.

Inner electrode 302 in producer 320 may be of unitary construction andhave no brazed or soldered part. Producer 320 may be of unitaryconstruction and have no brazed or soldered part. In an embodiment, theelectrolyte 306 is oxide ion conducting. In embodiments, the electrolytemay comprise one or more materials previously listed herein forelectrolyte 206 in tubular reactor 200. In embodiments, the electrodes302, 304 may comprise one or more materials previously listed herein fortubular structures 202, 204 in tubular reactor 200. In some embodiments,the producer 320 further comprises one or more interconnects.

FIG. 3C illustrates a cross section of a multi-tubular EC gas producer340, according to an embodiment of the disclosure. Gas producer 340 hasa rectangular-like shape cross-section. EC gas producer 340 comprises aninner electrode 302, an outer electrode 304, and an electrolyte 306between the electrodes 302, 304. In some embodiments, electrolyte 306 isreferred to as a membrane. The inner electrode 302 comprises multiplevoid spaces 308 joined in the axial direction of the tubular. Voidspaces 308 allow for fluid passage. The multiple tubular structure 340comprises multiple fluid passages 308 in the axial direction of thetubular structure 340. The cross-section of void spaces 308 may besquare-like or rectangular-like as shown in FIG. 3C or other similarshapes in a regular fashion wherein the cross-sectional area of eachvoid space is substantially identical. Producer 340 has a cross sectionhaving a length and a width, wherein the length is at least 2 times thewidth and the cross section is orthogonal to the axial direction oftubular.

Inner electrode 302 in producer 340 may be of unitary construction andhave no brazed or soldered part. Producer 340 may be of unitaryconstruction and have no brazed or soldered part. In an embodiment, theelectrolyte 306 is oxide ion conducting. In embodiments, the electrolytemay comprise one or more materials previously listed herein forelectrolyte 206 in tubular reactor 200. In embodiments, the electrodes302, 304 may comprise one or more materials previously listed herein fortubular structures 202, 204 in tubular reactor 200. In some embodiments,the producer 340 further comprises one or more interconnects.

FIG. 3D illustrates a cross section of an EC gas producer 360, accordingto an embodiment of the disclosure. Gas producer 360 has arectangular-like shape cross-section. EC gas producer 360 is similar togas producer 340 in FIG. 3C, except that the fluid passage 380 is singleas shown in FIG. 3D.

Manufacture of Tubular and Multi-Tubular EC Gas Producers

Further discussed herein is a method of making a tubular EC gas produceras illustrated by device 200, 300, 320, 340, and 360, which are mereexamples of some tubular designs. At least three methods are discussedherein regarding how to make the first tubular: extrusion method,substrate method, and the process as shown in FIG. 5A-5B.

In an embodiment, a method of making a tubular EC gas producer comprisesforming a first tubular structure by extrusion. In some embodiments, thefirst tubular structure is an inner electrode 202. The method furthercomprises depositing a layer on the outer cylindrical surface of thefirst tubular structure 202, wherein the layer comprises an electrolyte206, and depositing a second tubular structure 204 over the electrolyte206, wherein the electrolyte 206 is oxide ion conducting. In anembodiment, the first tubular structure 202 and the second tubularstructure 204 comprise a metallic phase that does not contain a platinumgroup metal when the device is in use. In an embodiment, the devicecomprises no interconnect and wherein the electrolyte is electronicallyconducting.

In another manufacturing method embodiment, a method comprises extrudingan inner tubular structure 202; sintering the inner tubular structure202 in a furnace or with EMR to form a first electrode; coating theouter surface of the inner tubular structure 202 with an electrolytematerial; sintering the electrolyte material in a furnace or EMR to forman electrolyte 206; coating the electrolyte 206 with an electrodematerial; sintering the electrode material in a furnace or usingelectromagnetic radiation (EMR) to form an outer tubular structure 204wherein the outer tubular structure 204 is a second electrode. In anembodiment, outer tubular structure 204 comprises doped or undoped ceriaand a material selected from the group consisting of Cu, CuO, Cu₂O, Ag,Ag₂O, Au, Au₂O, Au₂O₃, stainless steel, and combinations thereof; and issintered using EMR. In an embodiment, the method further comprisesreducing the outer tubular structure 204 or reducing the inner tubularstructure 202 or both tubular structures 202, 204. These methodsdescribe an “inside out” method wherein the first extruded layer is theinner electrode layer.

The following method describes an “outside in” method wherein the firstlayer formed is the outer tubular structure 204 or outer electrodelayer. The method comprises extruding an outer tubular structure 204;sintering the outer tubular structure 204 in a furnace or with EMR toform a first electrode; coating the inner surface of the outer tubularstructure 204 with an electrolyte material; sintering the electrolytematerial in a furnace or EMR to form an electrolyte 206; coating theinner surface of electrolyte 206 with an electrode material; sinteringthe electrode material in a furnace or using electromagnetic radiation(EMR) to form an inner tubular structure 202 wherein the inner tubularstructure 202 is a second electrode. In an embodiment, inner tubularstructure 202 comprises doped or undoped ceria and a material selectedfrom the group consisting of Cu, CuO, Cu₂O, Ag, Ag₂O, Au, Au₂O, Au₂O₃,stainless steel, and combinations thereof; and is sintered using EMR. Inan embodiment, the method further comprises reducing the outer tubularstructure 204 or reducing the inner tubular structure 202 or bothtubular structures 202, 204.

In an embodiment, the coating steps for use in the “inside out” and“outside in” methods comprise dip coating, spraying, ultrasonicspraying, spin coating, brush coating, pasting, or combinations thereof.The electromagnetic radiation comprises UV light, near ultravioletlight, near infrared light, infrared light, visible light, laser,electron beam, microwave or combinations thereof. In an embodiment,electromagnetic radiation is provided by a xenon lamp. In someembodiments, the device may comprise one or more interconnects. In anembodiment, the inner tubular structure 202 and the outer tubularstructure 204 comprise one or more fluid channels or one or more fluiddispersing components or both fluid channels and fluid dispersingcomponents.

In another embodiment, the inner tubular structure 202 or the outertubular structure 204 may be formed from particulates and not fromliquid precursors, especially when the inner tubular structure 202 orthe outer tubular structure 204 comprises doped or undoped ceria and amaterial selected from the group consisting of Cu, CuO, Cu₂O, Ag, Ag₂O,Au, Au₂O, Au₂O₃, stainless steel, and combinations thereof. Theparticulates are suspended in a liquid before being deposited or coated,such as dip coating, spraying, spin coating, brush coating, pasting, orcombinations thereof. In such cases, the inner tubular structure 202 orthe outer tubular structure 204 is sintered using electromagneticradiation (EMR).

In other embodiments, a first tubular-like substrate is provided. Thetubular substrate is substantially in a desired shape of an EC gasproducer. In a first embodiment, a first electrode material is depositedon the outside of the tubular substrate. The first electrode material issintered to form an inner electrode 202. An electrolyte material is thendeposited on the inner electrode layer 202 surface. The electrolytematerial is the sintered to form an electrolyte 206. A second electrodematerial is then deposited on the electrolyte 206. The second electrodematerial is then sintered to form an outer electrode 204. This methodmay be described as an “inside out substrate method” wherein the firstlayer formed on the substrate is the inner electrode layer 202 followedby the electrolyte 206 layer then the outer electrode layer 204. Thefirst and second electrodes may be an anode or cathode. Sintering maycomprise thermal or EMR sintering.

In another similar method, a tubular-like substrate is provided. A firstelectrode material is deposited on the inside of the tubular substrate.The first electrode material is sintered to form an outer electrode 204.An electrolyte material is then deposited on the outer electrode layer204 surface. The electrolyte material is the sintered to form anelectrolyte 206. A second electrode material is then deposited on theelectrolyte 206. The second electrode material is then sintered to forman inner electrode 202. This method may be described as an “outside insubstrate method” wherein the first layer formed on the substrate is theinner electrode layer 202 followed by the electrolyte 206 layer then theouter electrode layer 204. The first and second electrodes may be ananode or cathode. Sintering may comprise thermal or EMR sintering.

In some embodiments, the substrate may then be removed once the finalelectrode is formed. The substrate may be removed by physical means. Thesubstrate may be dissolved and removed by means of a solvent. In somemethods, the substrate may be comprised of a low melting material suchas a polymer, wherein the substrate may be melted or gasified andremoved during any one of a thermal sintering step. For example, thesubstrate may comprise a combustible material such that during one ofthe thermal sintering steps the substrate is burned away.

In an embodiment, the first tubular (inner or outer) and the electrolyteare sintered in an oven separately. In an embodiment, the first tubular(inner or outer) and the electrolyte are co-sintered in an oven, whichmeans that the first tubular is coated with the electrolyte materialbefore being sintered. The second tubular (outer or inner) is depositedon the electrolyte and then sintered using EMR, wherein the secondtubular comprises doped or undoped ceria and a material selected fromthe group consisting of Cu, CuO, Cu₂O, Ag, Ag₂O, Au, Au₂O, Au₂O₃,stainless steel, and combinations thereof. FIGS. 4A-4D illustratevarious arrangements to sinter a tubular using an EMR source. The EMRsource and the tubular may move relative to one another, e.g., in theaxial direction or in a spiraling trajectory, to ensure the entiresurface of the tubular (inner or outer) is sintered by sufficientlyexposing it to the EMR source. In an embodiment, the EMR source is axenon lamp, such as a circular xenon lamp, a long tubular xenon lamp, apoint tubular xenon lamp.

FIGS. 4A-4D illustrate sintering methods and systems for manufacturingtubular EC gas producers using EMR. FIG. 4A illustrates a portion of amethod of manufacture 400 of an EC gas producer using a single point EMRsource, according to an embodiment of the disclosure. The EMR source(e.g., a xenon lamp) 402 and the tubular structure 404 can move relativeto one another. As shown in FIG. 4A, the single point EMR 402 may rotatearound the tubular structure 404 (e.g., in a spiral-like trajectory) ineither direction as denoted by arrow 406. Alternatively, the tubularstructure 404 may rotate around the single point EMR 402. In anotherembodiment, the tubular structure 404 may rotate around its own axis 408or move in an up or down direction 410 along its own long axis or acombination thereof. The single point EMR source 402 may also move in anup or down direction 412.

FIG. 4B illustrates a portion of a method of manufacture 420 of an ECgas producer using a ring-lamp EMR source, according to an embodiment ofthe disclosure. As shown in FIG. 4B, a circular ring-like lamp (e.g.,xenon lamp) 422 is shown as the EMR source with a hollow circle in thecenter. The tubular structure 404 is placed in the center of thecircular ring lamp 422. In some embodiments, the tubular structure 404may move up or down 410 or rotate 408 around its own axis while the ringlamp is 422 held in a stationary manner. In other embodiments, tubularstructure 404 may be held in a stationary manner while ring lamp 422 maymove along the length of tubular structure 404. Ring lamp 422 may movein an up or down 424 manner or in a manner which it rotates (426) on itsown axis to assure complete and thorough sintering. In otherembodiments, both the tubular structure 402 and the ring lamp 422 mayboth be able to move relative to each other to ensure the entire tubularstructure 404 is thoroughly and completely sintered. FIG. 4A-4Billustrate embodiments where the outer surface of the tubular structure404 is sintered via EMR. These methods may be used to sinter anodes,cathodes, electrolytes and other components of tubular EC gas producers.

FIGS. 4C-4D illustrate the embodiment wherein the inner surface of thetubular structure 404 is sintered via EMR. FIG. 4C illustrates a portionof a method of manufacturing 440 of an EC gas producer using a singlepoint EMR source, according to an embodiment of the disclosure. FIG. 4Cillustrates a single point EMR source (e.g., a xenon lamp) 402 that isplaced inside a tubular structure 404. In a first embodiment, thetubular structure 404 may be held in a stationary manner while thesingle point EMR source may be moved in an up or down 412 manner. In apreferred embodiment, single point EMR source 402 may irradiatesubstantially equally in all directions. In another embodiment, singlepoint EMR source may be held in a stationary manner while tubularstructure 404 may be moved in an up or down direction 410 or rotated 408about its own axis. In another embodiment, the tubular structure 404 andthe single point EMR source 402 both move relative to one another suchthat the entire inner surface of the tubular structure 404 is thoroughlyand substantially sintered.

FIG. 4D illustrates a portion of a method of manufacturing 460 of an ECgas producer using a tubular EMR source, according to an embodiment ofthe disclosure. FIG. 3E4D illustrates a cylindrical lamp as the EMRsource (e.g., a tubular xenon lamp) 462 that is placed inside thetubular structure 404 to be sintered. The length of the lamp in thiscase is such that the entire inner surface of the tubular structure 404may be sintered without the tubular lamp 462 and the tubular structure404 needing to move relative to one another. In one embodiment, tubularlamp 462 may be held in a stationary manner while tubular structure 404may be moved over the lamp 462. Tubular structure 404 may be moved in anup or down manner 464. For example, unsintered tubular structure 404 maybe moved over tubular lamp 462 into a specified position, remain in thisposition until sufficient radiation is carried out and tubular structure404 is substantially sintered, then moved in an up or down direction asdenoted by arrow 464 off of the tubular lamp 462 for the nextmanufacturing step. In another embodiment, unsintered tubular structure404 may be held in a stationary position while tubular lamp EMR source462 is moved into the tubular structure 404. Tubular lamp 462 may bemoved in an up or down fashion as denoted by arrows 464. The tubularstructure 404 may be formed using any suitable method, such as themethods discussed herein. For the embodiments of FIG. 4C-4D, coating andsintering take place on the inner surface of the tubular structure 404.

Many variations are possible for sintering as illustrated in FIGS.4A-4D. For example, an outer tubular structure 204 may be formed andthermally sintered in a furnace to form an anode or a cathode. Anelectrolyte material may then be coated on the inner surface of theouter tubular structure 204 and then sintered in a furnace or using asingle point EMR 402 or tubular lamp EMR 462 inside of the tubularstructure to form an electrolyte 206. Another electrode material maythen be coated on the inner surface of the electrolyte 206 and thensintered in a furnace or using EMR source 402, 462 to form an innertubular structure 202 such as an anode or cathode. For example, for acopper, gold, or silver-containing anode, the inner electrode issintered using an EMR source. For example, for Ni or NiO-containinganode, the inner electrode is sintered in a furnace or by an EMR source.

In some embodiments, a combination of an EMR source inside of a tubularelectrode 202, 204 or electrolyte 206 and an EMR source on the outsideof a tubular electrode 202, 204 or electrolyte 206 may be usedsimultaneously to sinter. For example, a tubular EMR source 462 and aring-like EMR source 422 may be used in the same sintering device tosinter sequentially or simultaneously.

FIGS. 5A-5B Illustrates another method to form the first tubular ormulti-tubular in EC gas producers. FIG. 5A illustrates a first step in atape casting method 500 to form a tubular or multi-tubular EC gasproducer, according to an embodiment of the disclosure. In a first step,supports 504 are placed onto a substrate 502, wherein the height of thesupports 504 is preconfigured to ensure a desirable thickness of thetubular electrode 506 on the bottom side. The substrate 502 and thesupports 504 may be made of metal, glass, plastic, wood, or any suitablematerial as known in the art. An electrode material 506 in a dispersionor slurry form is deposited on the substrate 502 between the supports504. The term slurry will be used in the description, but a dispersionmay also be used interchangeably. One or more spacers 508 are thenplaced on top of the slurry 506 and rested on supports 504. View 501 isan overhead view or top view further illustrating and showing an exampleof how the substrate 502, supports 504, electrode material 506 andspacers 508 may be arranged.

FIG. 5B illustrates steps 2-4 in a tape casting method 500 to form afirst tubular or a first multi-tubular in an EC gas producer, accordingto an embodiment of the disclosure. In step 2 additional slurry 510 isdeposited to cover the spacer(s) 508 and the previously deposited slurry506. A blade, such as a doctor blade, may be used to scrape across thetop of the additional slurry 510 to ensure a suitable thickness of thetubular electrode on the top side. In a preferred embodiment, the slurrycontains mainly organic solvent.

Step 3 illustrated in FIG. 5B includes immersing the substrate 502,supports 504, spacer(s) 508, the first slurry 506 and second slurry 510are immersed in deionized water to allow phase inversion of the slurryto take place. Phase inversion is a form of precipitation when theslurry comprising a lower polarity organic solvent is placed into higherpolarity deionized water. The components of the slurry precipitate outas a result since the components are not compatible with water.

The substrate 502 and supports 504 are then removed from the slurry 506,510 as a whole after the phase inversion. The slurry 506, 510 is allowedto dry (e.g., in ambient air) to remove excess deionized water. Then thespacers 508 are removed, being pulled out from either end. The electrodematerial 506, 510 is sintered to form the first tubular electrode 512with fluid passages 514. The spacers 508 may have any regular orirregular shape as desired, such as circular, oval-like, square-like,diamond-like, trapezoidal, rectangular, triangular, pentagonal,hexagonal, octagonal or other various cross-sectional shapes orcombinations thereof. If the spacers 508 have a rectangular crosssection, the multiple joined tubular fluid passages 514 will have arectangular cross section as fluid passage 514 in the inner electrode512 as illustrated in FIG. 3C. As also can be seen in FIGS. 3C-3D, theinner electrode 302 has a cross section having a length and a width,wherein the length is at least 2 times the width and the cross sectionis orthogonal to the axial direction of the tubular. Similarly, thereactor has a cross section having a length and a width, wherein thelength is at least 2 times the width and the cross section is orthogonalto the axial direction of the tubular.

In an embodiment, the method illustrated in step 4 in FIG. 5B furthercomprises coating the outer surface of the first tubular electrode 512with an electrolyte material. The electrolyte material may then besintered to form an electrolyte 516 in a furnace or by usingelectromagnetic radiation. Step 4 further comprises coating theelectrolyte 516 with a second electrode material. The second electrodematerial may be sintered in a furnace or using electromagnetic radiationto form a second outer tubular electrode 518. In an embodiment, thesecond electrode material comprises doped or undoped ceria and amaterial selected from the group consisting of Cu, CuO, Cu₂O, Ag, Ag₂O,Au, Au₂O, Au₂O₃, stainless steel, and combinations thereof; and it issintered using EMR to form the second outer tubular electrode 518. In anembodiment, the method comprises reducing the second outer tubularelectrode 518 or reducing the first inner tubular electrode 512 or both.

In an embodiment, the coating step comprises dip coating, spraying,ultrasonic spraying, spin coating, brush coating, pasting, orcombinations thereof. In an embodiment, electromagnetic radiationcomprises UV light, near ultraviolet light, near infrared light,infrared light, visible light, laser, electron beam, microwave, orcombinations thereof. In an embodiment, electromagnetic radiation isprovided by a xenon lamp. In an embodiment, the first tubular electrode512 has a cross section having a length and a width, wherein the lengthis at least 2 times the width and the cross section is orthogonal to theaxial direction of the tubular fluid passage 514. In an embodiment, theEC gas producer comprises no interconnect.

Operation of EC Gas Producer

Disclosed herein is a method comprising providing a device comprising afirst electrode, a second electrode, and an electrolyte between theelectrodes, introducing a first stream to the first electrode,introducing a second stream to the second electrode, extracting hydrogenfrom the second electrode, wherein the first electrode and the secondelectrode comprise a metallic phase that does not contain a platinumgroup metal when the device is in use. In an embodiment, the electrolyteis oxide ion conducting. In an embodiment, the device is operated at atemperature no less than 500° C., or no less than 600° C., or no lessthan 700° C. In an embodiment, the first stream comprises a fuel andwater or a fuel and carbon dioxide. In an embodiment, said fuelcomprises a hydrocarbon or hydrogen or carbon monoxide or combinationsthereof. In an embodiment, the first stream is directly introduced intothe first electrode or the second stream is directly introduced intosecond electrode or both.

In an embodiment, the first stream comprises a fuel with little to nowater. In an embodiment, the fuel comprises a hydrocarbon or hydrogen orcarbon monoxide or combinations thereof. In an embodiment, the secondstream consists of water and hydrogen.

In an embodiment, the method comprises providing a reformer upstream ofthe first electrode, wherein the first stream passes through thereformer before being introduced to the first electrode, wherein thefirst electrode comprises Ni or NiO. In an embodiment, the reformer is asteam reformer or an autothermal reformer.

In an embodiment, the method comprises using the extracted hydrogen inone of Fischer-Tropsch (FT) reactions, dry reforming reactions, Sabatierreaction catalyzed by nickel, Bosch reaction, reverse water gas shiftreaction, electrochemical reaction to produce electricity, production ofammonia, production of fertilizer, electrochemical compressor forhydrogen storage, fueling hydrogen vehicles or hydrogenation reactionsor combinations thereof.

Herein disclosed is a method of producing hydrogen comprising providinga EC gas producer device, introducing a first stream comprising a fuelto the device, introducing a second stream comprising water to thedevice, reducing the water in the second stream to hydrogen, andextracting hydrogen from the device, wherein the first stream and thesecond stream do not come in contact with each other in the device. Inan embodiment, the first stream does not come in contact with thehydrogen. In an embodiment, the first stream and the second stream areseparated by a membrane in the device. In an embodiment, the fuelcomprises a hydrocarbon or hydrogen or carbon monoxide or combinationsthereof. In an embodiment, the second stream comprises hydrogen. In anembodiment, the first stream comprises the fuel and water or the fueland carbon dioxide. In an embodiment, the first stream comprises thefuel with little to no water.

Hydrogen Production System

Further discussed herein is a hydrogen production system comprising afuel source; a water source; a hydrogen producer; wherein the fuelsource and the water source are in fluid communication with the producerand wherein the fuel and the water do not come in contact with eachother in the producer. The system may not include an external heatsource. In an embodiment, the fuel and the water do not come in contactwith each other in the system. In an embodiment, the producer comprisesa first electrode, a second electrode, and an electrolyte between thefirst and second electrodes; wherein the fuel source is in fluidcommunication with the first electrode and the water source is in fluidcommunication with the second electrode. In an embodiment, the fuelsource provides heat for the hydrogen producer and the hydrogen producerhas no additional heat source.

In an embodiment, the electrolyte comprises YSZ, CGO, LSGM, SSZ, SDC,ceria, lanthanum chromite, or combinations thereof or wherein theelectrolyte comprises doped or undoped ceria and optionally a materialselected from the group consisting of YSZ, LSGM, SSZ, and combinationsthereof. In an embodiment, the lanthanum chromite comprises undopedlanthanum chromite, strontium doped lanthanum chromite, iron dopedlanthanum chromite, lanthanum calcium chromite, or combinations thereof.The electrolyte may further comprise any material listed for electrolyte206 in the “Tubular and Multi-Tubular EC Gas Producers” section herein.In an embodiment, the electrolyte comprises doped ceria or wherein theelectrolyte comprises lanthanum chromite or a conductive metal orcombination thereof and a material selected from the group consisting ofdoped ceria, YSZ, LSGM, SSZ, and combinations thereof. In an embodiment,the lanthanum chromite comprises undoped lanthanum chromite, strontiumdoped lanthanum chromite, iron doped lanthanum chromite, lanthanumcalcium chromite, or combinations thereof. In an embodiment, theconductive metal comprises Ni, Cu, Ag, Au, or combinations thereof.

In an embodiment, the first electrode and the second electrode compriseNi or NiO and a material selected from the group consisting of YSZ, CGO,samaria-doped ceria (SDC), scandia-stabilized zirconia (SSZ), LSGM, andcombinations thereof. In an embodiment, the first electrode comprisesdoped or undoped ceria and a material selected from the group consistingof Cu, CuO, Cu₂O, Ag, Ag₂O, Au, Au₂O, Au₂O₃, stainless steel, andcombinations thereof; wherein the second electrode comprises Ni or NiOand a material selected from the group consisting of YSZ, CGO,samaria-doped ceria (SDC), scandia-stabilized zirconia (SSZ), LSGM, andcombinations thereof. The first electrode and second electrode maycomprise any material listed for the inner tubular structure 202 orouter tubular structure 204 in the “Tubular and Multi-Tubular EC GasProducers” section herein.

In an embodiment, the system comprises an oxidant source and a boiler,wherein the boiler is in fluid communication with the oxidant source,the water source, and the producer. In an embodiment, the boiler is inthermal communication with the producer, fuel input into the producer,the oxidant, the water, or combinations thereof. In an embodiment, theboiler is configured to receive exhaust from the first electrode of theproducer and to feed steam into the second electrode of the producer. Inan embodiment, the fuel is partially oxidized in the producer andfurther oxidized in the boiler. In an embodiment, the system comprises asteam turbine between the boiler and the producer and in fluidcommunication with the boiler and the producer.

In an embodiment, water is reduced in the producer to generate hydrogen.In an embodiment, the system comprises a condenser configured to receiveexhaust from the second electrode of the producer and to recycle waterto the boiler and to output hydrogen. In an embodiment, the condenser isin thermal communication with the fuel. In an embodiment, the systemcomprises a desulfurization unit between the fuel source and theproducer and in fluid communication with the fuel source and theproducer. In an embodiment, the producer is configured to have a fuelinlet temperature no greater than 1000° C. or no greater than 900° C. orfrom 800° C. to 850° C. In an embodiment, the producer is configured tohave a fuel outlet temperature no less than 600° C.

FIG. 6A, illustrates an example of a hydrogen production system 600 withno external heat source, according to an embodiment of the disclosure.The system 600 comprises a water source 602, an air/oxidant source 604,a fuel (e.g., methane) source 606, a hydrogen producer 608, and a boiler610. The system 600 generates hydrogen 612 and exhaust. The hydrogenproducer 608 comprises an anode and a cathode separated by anelectrolyte. The anode and cathode receive fuel and water respectivelyand the fuel and water do not come in contact with each other in theproducer 608. In various cases, the fuel and water do not come incontact with each other in the entire system 600. The heating burden isfully met by the system itself with no need for any external heatsource. For example, the boiler 610 heats the fuel input stream into theproducer 608, the producer 608, the oxidant 604, and the water 602. Theproducer 608 in operation has a fuel inlet temperature of no greaterthan 1000° C. or no greater than 900° C. or from 800° C. to 850° C. andhas a fuel outlet temperature no less than 600° C.

The fuel exits the fuel source 606 as stream 600-1, passes through adesulfurization unit 614 and becomes stream 600-2. Stream 600-2 entersthe condenser 616 and functions as the coolant for the condenser 616 andexits as stream 600-3, which is pre-heated fuel. Stream 600-3 enters aheat exchanger (HX2) 618 and is further heated by the exhaust stream600-6 from the boiler 610 to a proper temperature and enters theproducer 608 as stream 600-4. Stream 600-4 is received by the anode inthe producer 608 and is partially oxidized and then exits the producer608 as stream 600-5. Stream 600-5 is introduced into the boiler 610 andfurther oxidized by an oxidant in the boiler 610, generating heat as aresult. The exhaust from the boiler 610 exits as stream 600-6, passesthrough heat exchanger HX2 618 to heat the fuel input into the producer608 and becomes stream 600-7. Stream 600-7 heats the producer 608 toensure proper operation temperatures for the producer 608 and becomesstream 600-19. Stream 600-19 passes through heat exchanger HX1 620 toheat the oxidant and exits as stream 600-20. Stream 600-20 passesthrough heat exchanger HX3 622 to heat the water and exits as stream600-21.

Water exits the water source as stream 600-8, passes through a pump andbecomes stream 600-9. Stream 600-9 is heated in heat exchanger HX3 622by stream 600-20 and becomes stream 600-10. Stream 600-10 enters theboiler 610 and becomes steam (stream 600-11) by the heat generated fromthe oxidation reactions in the boiler 610. Stream 600-11 passes througha turbine 624 and becomes stream 600-12. The turbine 624 is utilized topower the pump. Stream 600-12 enters the hydrogen producer 608 and isreceived by the cathode of the producer 608. Water/steam is reduced tohydrogen at the cathode. A mixture of steam and hydrogen exits theproducer 608 as stream 600-13. Stream 600-13 enters the condenser 616and is cooled by the unheated fuel (stream 600-2). Water drops out ofthe mixture and is recycled from the condenser as stream 600-18. Stream600-18 joins stream 600-9 and reenters the boiler 610 after passingthrough heat exchangers HX3 622. Hydrogen exits the condenser as 616stream 600-14.

Air exits the oxidant source as stream 600-15 and passes through an aircleaner 626, where particulates and/or oxides are removed, and becomesstream 600-16. Stream 600-16 is heated in heat exchanger HX1 620 bystream 600-19 and becomes stream 600-17. Stream 600-17 enters the boiler610 and reacts with stream 600-5 to further oxidize the fuel andgenerate heat. The reaction products exit the boiler 610 as stream600-6.

FIG. 6B illustrates an alternative hydrogen production system 650 withno external heat source, according to an embodiment of the disclosure.Steam generator (SG) 652 serves similar functions as the boiler 610 insystem 600 in FIG. 6A. Air enters the condenser as stream 650-1 and isused as coolant in the condenser 616. Air stream 650-2 is then heated inheat exchanger HX1 620 before entering the hydrogen producer 608 asstream 650-3 and mixing with the anode output stream. The fuel enters asstream 650-4 and is heated in heat exchanger HX2 618 by the exhaustbefore entering the hydrogen producer 608 as stream 650-5. The fuel isoxidized in the anode of the hydrogen producer 608, becomes anode outputstream, and is further oxidized by air to become exhaust 650-6. Theexhaust provides thermal energy to the heat exchangers (HX1 620 and HX2618) and to SG 652 to produce steam from water. Steam enters thehydrogen producer 608 and is reduced to hydrogen at the cathode. Thecathode output stream 650-7 is introduced to the condenser 616. Waterfrom the condenser 616 is recycled as stream 650-8 and hydrogen isextracted from the condenser 616.

Fuel Cell

A fuel cell is an electrochemical apparatus that converts the chemicalenergy from a fuel into electricity through an electrochemical reaction.As mentioned above, there are many types of fuel cells, e.g.,proton-exchange membrane fuel cells (PEMFCs), solid oxide fuel cells(SOFCs). A fuel cell typically comprises an anode, a cathode, anelectrolyte, an interconnect, optionally a barrier layer and/oroptionally a catalyst. Both the anode and the cathode are electrodes.The listings of material for the electrodes, the electrolyte, and theinterconnect in a fuel cell are applicable in some cases to the EC gasproducer and the EC compressor. These listings are only examples and notlimiting. Furthermore, the designations of anode material and cathodematerial are also not limiting because the function of the materialduring operation (e.g., whether it is oxidizing or reducing) determineswhether the material is used as an anode or a cathode.

FIGS. 7-8 illustrate various embodiments of the components in a fuelcell or a fuel cell stack. In these embodiments, the anode, cathode,electrolyte, and interconnect are cuboids or rectangular prisms.

FIG. 7 illustrates a fuel cell component, according to an embodiment ofthe disclosure. Layer 701 schematically illustrates an anode, layer 702represents a cathode, layer 703 represents an electrolyte, layers 704represents barrier layers, layer 705 represents a catalyst and layer 706represents an interconnect.

FIG. 8 schematically illustrates two fuel cells in a fuel cell stack,according to an embodiment of the disclosure. The two fuel cells aredenoted “Fuel Cell 1” and “Fuel Cell 2”. Each fuel cell in FIG. 8comprises an anode layer 801, cathode layer 802, electrolyte layer 803,barrier layers 804, catalyst layer 805 and interconnect layer 806. Twofuel cell repeat units or two fuel cells form a stack as illustrated. Asis seen, on one side interconnect 806 is in contact with the largestsurface of cathode 802 of fuel cell 2 (or fuel cell repeat unit) and onthe opposite side interconnect 806 is in contact with the largestsurface of catalyst 805 (optional) or the anode 801 of bottom fuel cell2 (or fuel cell repeat unit). These repeat units or fuel cells areconnected in parallel by being stacked atop one another and sharing aninterconnect in between via direct contact with the interconnect ratherthan via electrical wiring. This kind of configuration illustrated inFIG. 8 contrasts with segmented-in-series (SIS) type fuel cells.

Cathode

In some embodiments, the cathode comprises perovskites, such as LSC,LSCF or LSM. In some embodiments, the cathode comprises one or more oflanthanum, cobalt, strontium or manganite. In an embodiment, the cathodeis porous. In some embodiments, the cathode comprises one or more ofYSZ, nitrogen, nitrogen boron doped graphene, La0.6Sr0.4Co0.2Fe0.8O3,SrCo0.5Sc0.5O3, BaFe0.75Ta0.25O3, BaFe0.875Re0.125O3,Ba0.5La0.125Zn0.375NiO3, Ba0.75Sr0.25Fe0.875Ga0.125O3, BaFe0.125Co0.125,Zr0.75O3. In some embodiments, the cathode comprises LSCo, LCo, LSF,LSCoF, or a combination thereof. In some embodiments, the cathodecomprises perovskites LaCoO3, LaFeO3, LaMnO3, (La,Sr)MnO3, LSM-GDC,LSCF-GDC, LSC-GDC. Cathodes containing LSCF are suitable forintermediate-temperature fuel cell operation.

In some embodiments, the cathode comprises a material selected from thegroup consisting of lanthanum strontium manganite, lanthanum strontiumferrite, and lanthanum strontium cobalt ferrite. In preferredembodiments, the cathode comprises lanthanum strontium manganite.

Anode

In some embodiments, the anode comprises copper, nickel-oxide,nickel-oxide-YSZ, NiO-GDC, NiO-SDC, aluminum doped zinc oxide,molybdenum oxide, lanthanum, strontium, chromite, ceria, perovskites(such as, LSCF [La{1−x}Sr{x}Co{1−y}Fe{y}O₃] or LSM [La{1−x}Sr{x}MnO₃],where x is usually in the range of 0.15-0.2 and y is in the range of 0.7to 0.8). In some embodiments, the anode comprises SDC or BZCYYb coatingor barrier layer to reduce coking and sulfur poisoning. In anembodiment, the anode is porous. In some embodiments, the anodecomprises a combination of electrolyte material and electrochemicallyactive material or a combination of electrolyte material andelectrically conductive material.

In a preferred embodiment, the anode comprises nickel and yttriastabilized zirconia. In a preferred embodiment, the anode is formed byreduction of a material comprising nickel oxide and yttria stabilizedzirconia. In a preferred embodiment, the anode comprises nickel andgadolinium stabilized ceria. In a preferred embodiment, the anode isformed by reduction of a material comprising nickel oxide and gadoliniumstabilized ceria.

Electrolyte

In an embodiment, the electrolyte in a fuel cell comprises stabilizedzirconia (e.g., YSZ, YSZ-8, Y_(0.16)Zr_(0.84)O₂). In an embodiment, theelectrolyte comprises doped LaGaO3, (e.g., LSGM,La_(0.9)Sr_(0.1)Ga_(0.8)Mg0.2O₃). In an embodiment, the electrolytecomprises doped ceria, (e.g., GDC, Gd_(0.2)Ce_(0.8)O₂). In anembodiment, the electrolyte comprises stabilized bismuth oxide (e.g.,BVCO, Bi2V_(0.9)Cu_(0.1)O_(5.35)).

In some embodiments, the electrolyte comprises zirconium oxide, yttriastabilized zirconium oxide (also known as YSZ, YSZ8 (8 mole % YSZ)),ceria, gadolinia, scandia, magnesia or calcia or a combination thereof.In an embodiment, the electrolyte is sufficiently impermeable to preventsignificant gas transport and prevent significant electrical conduction;and allow ion conductivity. In some embodiments, the electrolytecomprises doped oxide such as cerium oxide, yttrium oxide, bismuthoxide, lead oxide, lanthanum oxide. In some embodiments, the electrolytecomprises perovskite, such as, LaCoFeO₃ or LaCoO₃ orCe_(0.9)Gd_(0.1)O₂(GDC) or Ce_(0.9)Sm_(0.1)O₂ (SDC, samaria doped ceria)or scandia stabilized zirconia or a combination thereof.

-   -   In some embodiments, the electrolyte comprises a material        selected from the group consisting of zirconia, ceria, and        gallia. In some embodiments, the material is stabilized with a        stabilizing material selected from the group consisting of        scandium, samarium, gadolinium, and yttrium. In an embodiment,        the material comprises yttria stabilized zirconia.

Interconnect

In some embodiments, the interconnect comprises silver, gold, platinum,AISI441, ferritic stainless steel, stainless steel, lanthanum, chromium,chromium oxide, chromite, cobalt, cesium, Cr₂O₃, or a combinationthereof. In some embodiments, the anode comprises a LaCrO₃ coating onCr₂O₃ or NiCo₂O₄ or MnCo₂O₄ coatings. In some embodiments, theinterconnect surface is coated with Cobalt and/or Cesium. In someembodiments, the interconnect comprises ceramics. In some embodiment,the interconnect comprises lanthanum chromite or doped lanthanumchromite. In an embodiment, the interconnect comprises a materialfurther comprising metal, stainless steel, ferritic steel, crofer,lanthanum chromite, silver, metal alloys, nickel, nickel oxide,ceramics, or lanthanum calcium chromite, or a combination thereof.

Catalyst

In various embodiments, the fuel cell comprises a catalyst, such as,platinum, palladium, scandium, chromium, cobalt, cesium, CeO₂, nickel,nickel oxide, zine, copper, titania, ruthenium, rhodium, MoS₂,molybdenum, rhenium, vanadium, manganese, magnesium or iron or acombination thereof. In various embodiments, the catalyst promotesmethane reforming reactions to generate hydrogen and carbon monoxidesuch that they may be oxidized in the fuel cell. Very often, thecatalyst is part of the anode, especially nickel anode which hasinherent methane reforming properties. In an embodiment, the catalyst isbetween 1%-5%, or 0.1% to 10% by mass. In an embodiment, the catalyst isused on the anode surface or in the anode. In various embodiments, suchanode catalysts reduce harmful coking reactions and carbon deposits. Invarious embodiments, simple oxide versions of catalysts or perovskitemay be used as catalysts. For example, about 2% mass CeO₂ catalyst isused for methane-powered fuel cells. In various embodiments, thecatalyst may be dipped or coated on the anode. In various embodiments,the catalyst is made by an additive manufacturing machine (AMM) andincorporated into the fuel cell using the AMM.

The unique manufacturing methods discussed herein have described theassembly of ultra-thin fuel cells and fuel cell stacks. Conventionally,to achieve structural integrity, the fuel cell has at least one thicklayer per repeat unit. This may be the anode (such as an anode-supportedfuel cell) or the interconnect (such as an interconnect-supported fuelcell). As discussed above, pressing or compression steps are typicallynecessary to assemble the fuel cell components to achieve gas tightnessand/or proper electrical contact in traditional manufacturing processes.As such, the thick layers are necessary not only because traditionalmethods (like tape casting) cannot produce ultra-thin layers but alsobecause the layers must be thick to endure the pressing or compressionsteps. The preferred manufacturing methods of this disclosure haveeliminated the need for pressing or compression. The preferredmanufacturing methods of this disclosure have also enabled the making ofultra-thin layers. The multiplicity of the layers in a fuel cell or afuel cell stack provides sufficient structural integrity for properoperation when they are made according to this disclosure.

Herein disclosed is a fuel cell comprising an anode no greater than 1 mmor 500 microns or 300 microns or 100 microns or 50 microns or no greaterthan 25 microns in thickness. The cathode no greater than 1 mm or 500microns or 300 microns or 100 microns or 50 microns or no greater than25 microns in thickness. The electrolyte no greater than 1 mm or 500microns or 300 microns or 100 microns or 50 microns or 30 microns inthickness. In an embodiment, the fuel cell comprises an interconnecthaving a thickness of no less than 50 microns. In some cases, a fuelcell comprises an anode no greater than 25 microns in thickness, acathode no greater than 25 microns in thickness, and an electrolyte nogreater than 10 microns or 5 microns in thickness. In an embodiment, thefuel cell comprises an interconnect having a thickness of no less than50 microns. In an embodiment, the interconnect has a thickness in therange of 50 microns to 5 cm.

In a preferred embodiment, a fuel cell comprises an anode no greaterthan 100 microns in thickness, a cathode no greater than 100 microns inthickness, an electrolyte no greater than 20 microns in thickness, andan interconnect no greater than 30 microns in thickness. In a morepreferred embodiment, a fuel cell comprises an anode no greater than 50microns in thickness, a cathode no greater than 50 microns in thickness,an electrolyte no greater than 10 microns in thickness, and aninterconnect no greater than 25 microns in thickness. In an embodiment,the interconnect has a thickness in the range of 1 micron to 20 microns.

In a preferred embodiment, the fuel cell comprises a barrier layerbetween the anode and the electrolyte, or a barrier layer between thecathode and the electrolyte, or both barrier layers. In some cases, thebarrier layers are the interconnects. In such cases, the reactants aredirectly injected into the anode and the cathode.

In an embodiment, the cathode has a thickness of no greater than 15microns, or no greater than 10 microns, or no greater than 5 microns. Inan embodiment, the anode has a thickness no greater than 15 microns, orno greater than 10 microns, or no greater than 5 microns. In anembodiment, the electrolyte has a thickness of no greater than 5microns, or no greater than 2 microns, or no greater than 1 micron, orno greater than 0.5 micron. In an embodiment, the interconnect is madeof a material comprising metal, stainless steel, silver, metal alloys,nickel, nickel oxide, ceramics, lanthanum chromite, doped lanthanumchromite, or lanthanum calcium chromite. In an embodiment, the fuel cellhas a total thickness of no less than 1 micron.

Also discussed herein is a fuel cell stack comprising a multiplicity offuel cells, wherein each fuel cell comprises an anode no greater than 25microns in thickness, a cathode no greater than 25 microns in thickness,an electrolyte no greater than 10 microns in thickness, and aninterconnect having a thickness in the range from 100 nm to 100 microns.In an embodiment, each fuel cell comprises a barrier layer between theanode and the electrolyte, or a barrier layer between the cathode andthe electrolyte, or both barrier layers. In an embodiment, the barrierlayers are the interconnects. For example, the interconnect is made ofsilver. For example, the interconnect has a thickness in the range from500 nm to 1000 nm. In an embodiment, the interconnect is made of amaterial comprising metal, stainless steel, silver, metal alloys,nickel, nickel oxide, ceramics, or lanthanum calcium chromite.

In an embodiment, the cathode has a thickness of no greater than 15microns, or no greater than 10 microns, or no greater than 5 microns. Inan embodiment, the anode has a thickness of no greater than 15 microns,or no greater than 10 microns, or no greater than 5 microns. In anembodiment, the electrolyte has a thickness of no greater than 5microns, or no greater than 2 microns, or no greater than 1 micron, orno greater than 0.5 micron. In an embodiment, each fuel cell has a totalthickness of no less than 1 micron.

Further discussed herein is a method of making a fuel cell comprising(a) forming an anode no greater than 25 microns in thickness, (b)forming a cathode no greater than 25 microns in thickness, and (c)forming an electrolyte no greater than 10 microns in thickness. In anembodiment, steps (a)-(c) are performed using additive manufacturing. Invarious embodiments, said additive manufacturing employs one or more ofextrusion, photopolymerization, powder bed fusion, material jetting,binder jetting, directed energy deposition or lamination.

In an embodiment, the method comprises assembling the anode, thecathode, and the electrolyte using additive manufacturing. In anembodiment, the method comprises forming an interconnect and assemblingthe interconnect with the anode, the cathode, and the electrolyte.

In preferred embodiments, the method comprises making at least onebarrier layer. In preferred embodiments, the at least one barrier layeris used between the electrolyte and the cathode or between theelectrolyte and the anode, or both. In an embodiment, the at least onebarrier layer also acts as an interconnect.

In preferred embodiments, the method comprises heating the fuel cellsuch that shrinkage rates of the anode, the cathode, and the electrolyteare matched. In some embodiments, such heating takes place for nogreater than 30 minutes, preferably no greater than 30 seconds, and mostpreferably no greater than 30 milliseconds. When a fuel cell comprises afirst composition and a second composition, wherein the firstcomposition has a first shrinkage rate and the second composition has asecond shrinkage rate, the heating described in this disclosurepreferably takes place such that the difference between the firstshrinkage rate and the second shrinkage rate is no greater than 75% ofthe first shrinkage rate.

In a preferred embodiment, the heating employs electromagnetic radiation(EMR). In various embodiments, EMR comprises UV light, near ultravioletlight, near infrared light, infrared light, visible light, laser,electron beam. Preferably, heating is performed in situ.

Also disclosed herein is a method of making a fuel cell stack comprisinga multiplicity of fuel cells, the method comprising: (a) forming ananode no greater than 25 microns in thickness in each fuel cell, (b)forming a cathode no greater than 25 microns in thickness in each fuelcell, (c) forming an electrolyte no greater than 10 microns in thicknessin each fuel cell, and (d) producing an interconnect having a thicknessof from 100 nm to 100 microns in each fuel cell.

In an embodiment, steps (a)-(d) are performed using AM. In variousembodiments, AM employs one or more of processes of extrusion,photopolymerization, powder bed fusion, material jetting, binderjetting, directed energy deposition or lamination.

In an embodiment, the method of making a fuel cell stack comprisesassembling the anode, the cathode, the electrolyte, and the interconnectusing AM. In an embodiment, the method comprises making at least onebarrier layer in each fuel cell. In an embodiment, the at least onebarrier layer is used between the electrolyte and the cathode or betweenthe electrolyte and the anode or both. In an embodiment, the at leastone barrier layer also acts as the interconnect.

In an embodiment, the method of making a fuel cell stack comprisesheating each fuel cell such that shrinkage rates of the anode, thecathode, and the electrolyte are matched. In an embodiment, such heatingtakes place for no greater than 30 minutes, or no greater than 30seconds, or no greater than 30 milliseconds. In a preferred embodiment,said heating comprises one or more of electromagnetic radiation (EMR).In various embodiments, EMR comprises UV light, near ultraviolet light,near infrared light, infrared light, visible light, laser, electronbeam. In an embodiment, heating is performed in situ.

In an embodiment, the method comprises heating the entire fuel cellstack such that shrinkage rates of the anode, the cathode, and theelectrolyte are matched. In some embodiments, such heating takes placefor no greater than 30 minutes, or no greater than 30 seconds, or nogreater than 30 milliseconds.

Herein discussed is a method of making an electrolyte comprising (a)formulating a colloidal suspension, wherein the colloidal suspensioncomprises an additive, particles having a range of diameters and a sizedistribution, and a solvent; (b) forming an electrolyte comprising thecolloidal suspension; and (c) heating at least a portion of theelectrolyte; wherein formulating the colloidal suspension is preferablyoptimized by controlling the pH of the colloidal suspension, orconcentration of the binder in the colloidal suspension, or compositionof the binder in the colloidal suspension, or the range of diameters ofthe particles, or maximum diameter of the particles, or median diameterof the particles, or the size distribution of the particles, or boilingpoint of the solvent, or surface tension of the solvent, or compositionof the solvent, or thickness of the minimum dimension of theelectrolyte, or the composition of the particles, or combinationsthereof.

Herein discussed is a method of making a fuel cell comprising (a)obtaining a cathode and an anode; (b) modifying the cathode surface andthe anode surface; (c) formulating a colloidal suspension, wherein thecolloidal suspension comprises an additive, particles having a range ofdiameters and a size distribution, and a solvent; (d) forming anelectrolyte comprising the colloidal suspension between the modifiedanode surface and the modified cathode surface; and (e) heating at leasta portion of the electrolyte; wherein formulating the colloidalsuspension comprises controlling pH of the colloidal suspension, orconcentration of the binder in the colloidal suspension, or compositionof the binder in the colloidal suspension, or the range of diameters ofthe particles, or maximum diameter of the particles, or median diameterof the particles, or the size distribution of the particles, or boilingpoint of the solvent, or surface tension of the solvent, or compositionof the solvent, or thickness of the minimum dimension of theelectrolyte, or the composition of the particles, or combinationsthereof. In various embodiments, the anode and the cathode are obtainedvia any suitable means. In an embodiment, the modified anode surface andthe modified cathode surface have a maximum height profile roughnessthat is less than the average diameter of the particles in the colloidalsuspension. The maximum height profile roughness 900 refers to themaximum distance between any trough 902 and an adjacent peak 904 of ananode surface or a cathode surface as illustrated in FIG. 9. In variousembodiments, the anode surface and the cathode surface are modified viaany suitable means.

Further disclosed herein is a method of making a fuel cell comprising(a) obtaining a cathode and an anode; (b) formulating a colloidalsuspension, wherein the colloidal suspension comprises an additive,particles having a range of diameters and a size distribution, and asolvent; (c) forming an electrolyte comprising the colloidal suspensionbetween the anode and the cathode; and (d) heating at least a portion ofthe electrolyte; wherein formulating the colloidal suspension comprisescontrolling pH of the colloidal suspension, or concentration of thebinder in the colloidal suspension, or composition of the binder in thecolloidal suspension, or the range of diameters of the particles, ormaximum diameter of the particles, or median diameter of the particles,or the size distribution of the particles, or boiling point of thesolvent, or surface tension of the solvent, or composition of thesolvent, or thickness of the minimum dimension of the electrolyte, orthe composition of the particles, or combinations thereof. In variousembodiments, the anode and the cathode are obtained via any suitablemeans. In an embodiment, the anode surface in contact with theelectrolyte and the cathode surface in contact with the electrolyte havea maximum height profile roughness that is less than the averagediameter of the particles in the colloidal suspension.

In a preferred embodiment, the solvent comprises water. In a preferredembodiment, the solvent comprises an organic component. The solvent maycomprise ethanol, butanol, alcohol, terpineol, diethyl ether1,2-dimethoxyethane (DME (ethylene glycol dimethyl ether), 1-propanol(n-propanol, n-propyl alcohol), or butyl alcohol or a combinationthereof. In some embodiments, the solvent surface tension is less thanhalf of water's surface tension in air. In an embodiment, the solventsurface tension is less than 30 mN/m at atmospheric conditions.

In some embodiments, the electrolyte is formed adjacent to a firstsubstrate or the electrolyte is formed between a first substrate and asecond substrate. In some embodiments, the first substrate has a maximumheight profile roughness that is less than the average diameter of theparticles. In some embodiments, the particles have a packing densitygreater than 40%, or greater than 50%, or greater than 60%. In anembodiment, the particles have a packing density close to the randomclose packing (RCP) density.

Random close packing (RCP) is an empirical parameter used tocharacterize the maximum volume fraction of solid objects obtained whenthey are packed randomly. A container is randomly filled with objects,and then the container is shaken or tapped until the objects do notcompact any further, at this point the packing state is RCP. The packingfraction is the volume taken by a number of particles in a given spaceof volume. The packing fraction determines the packing density. Forexample, when a solid container is filled with grain, shaking thecontainer will reduce the volume taken up by the objects, thus allowingmore grain to be added to the container. Shaking increases the densityof packed objects. When shaking no longer increases the packing density,a limit is reached and if this limit is reached without obvious packinginto a regular crystal lattice, this is the empirical randomclose-packed density.

In some embodiments, the median particle diameter is between 50 nm and1000 nm, or between 100 nm and 500 nm, or approximately 200 nm. In someembodiments, the first substrate comprises particles having a medianparticle diameter, wherein the median particle diameter of theelectrolyte may be no greater than 10 times and no less than 1/10 of themedian particle diameter of the first substrate. In some embodiments,the first substrate comprises a particle size distribution that isbimodal having a first mode and a second mode, each having a medianparticle diameter. In some embodiments, the median particle diameter inthe first mode of the first substrate is greater than 2 times, orgreater than 5 times, or greater than 10 times that of the second mode.The particle size distribution of the first substrate may be adjusted tochange the behavior of the first substrate during heating. In someembodiments, the first substrate has a shrinkage that is a function ofheating temperature. In some embodiments, the particles in the colloidalsuspension may have a maximum particle diameter and a minimum particlediameter, wherein the maximum particle diameter is less than 2 times, orless than 3 times, or less than 5 times, or less than 10 times theminimum particle diameter. In some embodiments, the minimum dimension ofthe electrolyte is less than 10 microns, or less than 2 microns, or lessthan 1 micron, or less than 500 nm.

In some embodiments, the electrolyte has a gas permeability of nogreater than 1 millidarcy, preferably no greater than 100 microdarcy,and most preferably no greater than 1 microdarcy. Preferably, theelectrolyte has no cracks penetrating through the minimum dimension ofthe electrolyte. In some embodiments, the boiling point of the solventis no less than 200° C., or no less than 100° C., or no less than 75° C.In some embodiments, the boiling point of the solvent is no greater than125° C., or no greater than 100° C., or no greater than 85° C., nogreater than 70° C. In some embodiments, the pH of the colloidalsuspension is no less than 7, or no less than 9, or no less than 10.

In some embodiments, the additive comprises polyethylene glycol (PEG),ethyl cellulose, polyvinylpyrrolidone (PVP), polyvinyl butyral (PVB),butyl benzyl phthalate (BBP), polyalkylene glycol (PAG) or a combinationthereof. In an embodiment, the additive concentration is no greater than100 mg/cm3, or no greater than 50 mg/cm3, or no greater than 30 mg/cm3,or no greater than 25 mg/cm3.

In an embodiment, the colloidal suspension is milled. In an embodiment,the colloidal suspension is milled using a rotational mill wherein therotational mill is operated at no less than 20 rpm, or no less than 50rpm, or no less than 100 rpm, or no less than 150 rpm. In an embodiment,the colloidal suspension is milled using zirconia milling balls ortungsten carbide balls wherein the colloidal suspension is milled for noless than 2 hours, or no less than 4 hours, or no less than 1 day, or noless than 10 days.

In some embodiments, the particle concentration in the colloidalsuspension is no greater than 30 wt %, or no greater than 20 wt %, or nogreater than 10 wt %. In other embodiments, the particle concentrationin the colloidal suspension is no less than 2 wt %. In some embodiments,the particle concentration in the colloidal suspension is no greaterthan 10 vol %, or no greater than 5 vol %, or no greater than 3 vol %,or no greater than 1 vol %. In an embodiment, the particle concentrationin the colloidal suspension is no less than 0.1 vol %.

In a preferred embodiment, the electrolyte is formed using an additivemanufacturing machine (AMM). In a preferred embodiment, the firstsubstrate is formed using an AMM. In a preferred embodiment, the heatingcomprises the use of electromagnetic radiation (EMR) wherein the EMRcomprises one or more of UV light, near ultraviolet light, near infraredlight, infrared light, visible light or laser. In a preferredembodiment, the first substrate and the electrolyte are heated to causeco-sintering. In a preferred embodiment, the first substrate, the secondsubstrate, and the electrolyte are heated to cause co-sintering. In anembodiment, the EMR is controlled to preferentially sinter the firstsubstrate over the electrolyte.

In an embodiment, the electrolyte is compresses after heating. In anembodiment, the first substrate and the second substrate applycompressive stress to the electrolyte after heating. In an embodiment,the first substrate and the second substrate that are applyingcompressive stress are the anode and cathode of a fuel cell. In someembodiments, the minimum dimension of the electrolyte is between 500 nmand 5 microns or between 1 micron and 2 microns.

The detailed discussion described herein uses the production of solidoxide fuel cells (SOFCs) as an illustrative example. As one in the artrecognizes, the methodology and the manufacturing process describedherein are applicable to all fuel cell types. As such, the production ofall fuel cell types is within the scope of this disclosure.

Reactor Cartridge

In various embodiments, an electrochemical (EC) reactor is formed into acartridge form. The discussion herein uses fuel cell or fuel cell stackas an example. The cartridge design is applicable to otherelectrochemical reactors, such as EC gas producer, EC compressor, flowbattery. In various embodiments, the fuel cell stack is configured to bemade into a cartridge form, such as an easily detachable flanged fuelcell cartridge (FCC) design. FIG. 9A illustrates a perspective view of afuel cell cartridge (FCC) 900, according to an embodiment of thedisclosure. FCC 900 comprises a rectangular shape as illustrated in FIG.9A. Other form factors are possible such as square-like,cylindrical-like, hexagonal-like or combinations thereof. The formfactor may depend on the application where the FCC may be used such asin industrial, home, automotive or other applications. FCC 900 alsocomprises holes for bolts 902 to secure the FCC in a system or in serieswith other FCCs, or both. FCC cartridge 900 housing may be comprised ofaluminum, steel, plastic, ceramics, or a combination thereof. FCC 900comprises a top interconnect 904.

FIG. 9B illustrates a perspective view of a cross-section of a fuel cellcartridge (FCC) 900, according to an embodiment of the disclosure. FCC900 comprises holes for bolts 902, cathode layer 906, barrier layer 908,anode layer 910, gas channels 912 in the electrodes (anode and cathode),electrolyte layer 914, an air heat exchanger 916, fuel heat exchanger918 and top interconnect 904. Air heat exchanger 916 and fuel heatexchanger 918 combined form an integrated multi-fluid heat exchanger. Insome embodiments, there is no barrier layer between the cathode 906 andthe electrolyte 914. FCC 900 comprises a second interconnect 920, suchas between anode layer 910 and fuel heat exchanger 918. FCC 900 furthercomprises openings 922, 924 for fuel passages.

FIG. 9C illustrates cross-sectional views of a fuel cell cartridge(FCC), according to an embodiment of the disclosure. FCC 900 in FIG. 9Ccomprises electrical bolt isolation 926, anode 910, seal 928 that sealsanode 910 from air flow, cathode 906 and seal 930 that seals cathode 906from fuel flow. The bolts may be isolated electrically with a seal aswell. In various embodiments, the seals may be dual functional seal(DFS) comprising YSZ (yttria-stabilized zirconia) or a mixture of 3YSZ(3 mol % Y₂O₃ in ZrO₂) and 8YSZ (8 mol % Y₂O₃ in ZrO₂). In someembodiments, the DFS is impermeable to non-ionic substances andelectrically insulating. In some embodiments, the mass ratio of3YSZ/8YSZ is in the range of from 10/90 to 90/10. In some embodiments,the mass ratio of 3YSZMYSZ is about 50/50. In some embodiments, the massratio of 3YSZ/BYSZ is 100/0 or 0/100.

FIG. 9D illustrates top view and bottom view of a fuel cell cartridge(FCC), according to an embodiment of the disclosure. FCC 900 comprisesholes for bolts 902, air inlet 932, air outlet 934, fuel inlet 922, fueloutlet 924, bottom 936 and top interconnect 904 of FCC 900. FIG. 9Dfurther illustrates the top view and bottom view of an embodiment of FCC900, in which the length of the oxidant side of FCC 900 is shown L_(o),the length of the fuel side of FCC 900 is shown L_(f), the width of theoxidant (air inlet 932) entrance is shown W_(o), and the width of thefuel inlet 922 is shown W_(f). In FIG. 9D, two fluid exits are shown(air outlet 934 and fuel outlet 924). In some embodiments, the anodeexhaust and the cathode exhaust may be mixed and extracted through onefluid exit. In some cases, bottom 936 is an interconnect and 932, 934,922, 924 are openings for fluid passage, e.g., in the directionperpendicular to the lateral direction.

Disclosed herein is a fuel cell cartridge (FCC) 900 comprising an anode910, a cathode 906, an electrolyte 914, at least one interconnect, afuel entrance on a fuel side of the FCC 900, an oxidant entrance on anoxidant side of the FCC, at least one fluid exit, wherein the fuelentrance has a width of W_(f), the fuel side of the FCC has a length ofL_(f), the oxidant entrance has a width of W_(o), the oxidant side ofthe FCC has a length of L_(o), wherein W_(f)/L_(f) is in the range of0.1 to 1.0, or 0.1 to 0.9, or 0.2 to 0.9, or 0.5 to 0.9, or 0.5 to 1.0and W_(o)/L_(o) is in the range of 0.1 to 1.0, or 0.1 to 0.9, or 0.2 to0.9, or 0.5 to 0.9, or 0.5 to 1.0.

In some embodiments, the air and fuel entrances and exits are on onesurface of the FCC 900 wherein the FCC 900 comprises no protruding fluidpassages on said surface. In some embodiments, the surface is smoothwith a maximum elevation change of no greater than 1 mm, or no greaterthan 100 microns, or no greater than 10 microns.

In some embodiments, an FCC 900 comprises a barrier layer between theelectrolyte and the cathode, or between the electrolyte and the anode,or both. In an embodiment, the FCC comprises a dual functional seal(DFS) that is impermeable to non-ionic substances and electricallyinsulating. In some embodiments, the DFS comprises YSZ(yttria-stabilized zircon a or a mixture of 3YSZ (3 mol % Y₂O₃ in ZrO₂)and 8YSZ (8 mol % Y₂O₃ in ZrO₂).

In some embodiments, the interconnect comprises no fluid dispersingelement and the anode and cathode comprise fluid dispersing components.In some embodiments, the interconnect comprises no fluid dispersingelement while the anode and cathode comprise fluid channels.

In some embodiments, a fuel cell cartridge (FCC) 900 comprising ananode, a cathode, an electrolyte, an interconnect, a fuel entrance, anoxidant entrance, at least one fluid exit, wherein the entrances andexit are on one surface of the FCC and the FCC comprises no protrudingfluid passage on the surface. In some embodiments, the surface may besmooth with a maximum elevation change of no greater than 1 mm, or nogreater than 100 microns, or no greater than 10 microns.

In some embodiments, the FCC 900 comprises a DFS that is impermeable tonon-ionic substances and electrically insulating. In an embodiment, theinterconnect comprises no fluid dispersing element and the anode andcathode comprise fluid dispersing components. In an embodiment, theinterconnect comprises no fluid dispersing element and said anode andcathode comprise fluid channels.

In an embodiment, the FCC 900 is detachably fixed to a mating surfaceand not soldered nor welded to said mating surface. In an embodiment,the FCC is bolted to or pressed to the mating surface. The matingsurface comprises a matching fuel entrance, matching oxidant entrance,and at least one matching fluid exit.

Further disclosed herein is an assembly comprising a fuel cell cartridge(FCC) and a mating surface, wherein the FCC comprises an anode, acathode, an electrolyte, an interconnect, a fuel entrance on a fuel sideof the FCC, an oxidant entrance on an oxidant side of the FCC, at leastone fluid exit, wherein the fuel entrance has a width of W_(f), the fuelside of the FCC has a length of L_(f), the oxidant entrance has a widthof W_(o), the oxidant side of the FCC has a length of L_(o), whereinW_(f)/L_(f) is in the range of 0.1 to 1.0, or 0.1 to 0.9, or 0.2 to 0.9,or 0.5 to 0.9, or 0.5 to 1.0 and W_(o)/L_(o) is in the range of 0.1 to1.0, or 0.1 to 0.9, or 0.2 to 0.9, or 0.5 to 0.9, or 0.5 to 1.0, whereinthe FCC is detachably fixed to the mating surface.

In some embodiments, said entrances and exits are on one surface of theFCC and wherein the FCC comprises no protruding fluid passage on saidsurface. The surface may be smooth with a maximum elevation change of nogreater than 1 mm, or no greater than 100 microns, or no greater than 10microns.

In an embodiment, said interconnect comprises no fluid dispersingelement and said anode and cathode comprise fluid dispersing components.In an embodiment, said interconnect comprises no fluid dispersingelement and said anode and cathode comprise fluid channels.

Discussed herein is a method comprising pressing or bolting together afuel cell cartridge (FCC) and a mating surface. The method excludeswelding or soldering together the FCC and the mating surface, whereinthe FCC comprises an anode, a cathode, an electrolyte, an interconnect,a fuel entrance on a fuel side of the FCC, an oxidant entrance on anoxidant side of the FCC, at least one fluid exit, wherein the fuelentrance has a width of W_(f), the fuel side of the FCC has a length ofL_(f), the oxidant entrance has a width of W_(o), the oxidant side ofthe FCC has a length of L_(o), wherein W_(f)/L_(f) is in the range of0.1 to 1.0, or 0.1 to 0.9, or 0.2 to 0.9, or 0.5 to 0.9, or 0.5 to 1.0and W_(o)/L_(o) is in the range of 0.1 to 1.0, or 0.1 to 0.9, or 0.2 to0.9, or 0.5 to 0.9, or 0.5 to 1.0, wherein the FCC and the matingsurface are detachable.

In an embodiment, said entrances and exit are on one surface of the FCCwherein the FCC comprises no protruding fluid passage on said surface.The surface is smooth with a maximum elevation change of no greater than1 mm, or no greater than 100 microns, or no greater than 10 microns. Inan embodiment, said interconnect comprises no fluid dispersing elementand said anode and cathode comprise fluid dispersing components. In anembodiment, said interconnect comprises no fluid dispersing element andsaid anode and cathode comprise fluid channels.

Herein disclosed is a fuel cell cartridge (FCC) comprising a fuel celland a fuel cell casing, wherein the fuel cell comprises an anode, acathode and an electrolyte, wherein at least a portion of the fuel cellcasing is made of the same material as the electrolyte. In anembodiment, the electrolyte is in contact with the portion of the fuelcell casing made of the same material. In an embodiment, the electrolyteand the portion of the fuel cell casing are made of a DFS, wherein theDFS comprises 3YSZ (3 mol % Y₂O₃ in ZrO₂) and 8YSZ (8 mol % Y₂O₃ inZrO₂), wherein the mass ratio of 3YSZ/8YSZ is in the range of from 100/0to 0/100 or from 10/90 to 90/10 and wherein the DFS is impermeable tonon-ionic substances and electrically insulating. In an embodiment, themass ratio of 3YSZ/8YSZ is about 50/50 or 40/60 or 60/40 or 30/70 or70/30 or 20/80 or 80/20.

In an embodiment, said fuel cell casing comprises a fuel entrance andfuel passage for the anode, an oxidant entrance and oxidant passage forthe cathode, and at least one fluid exit. In an embodiment, theentrances and at least one exit are on one surface of the FCC whereinthe FCC comprises no protruding fluid passage on the surface. In anembodiment, the fuel cell casing is in contact with at least a portionof the anode.

In an embodiment, the FCC comprises a barrier layer between theelectrolyte and the cathode and between the fuel cell casing and thecathode. In an embodiment, the FCC comprises an interconnect, whereinthe interconnect comprises no fluid dispersing element and said anodeand cathode comprise fluid dispersing components. In an embodiment, theFCC comprises an interconnect, wherein the interconnect comprises nofluid dispersing element and said anode and cathode comprise fluidchannels.

In an embodiment, the FCC is detachably fixed to a mating surface andnot soldered nor welded to said mating surface. In an embodiment, saidmating surface comprises matching fuel entrance, matching oxidantentrance, and at least one matching fluid exit.

Also discussed herein is a DFS comprising 3YSZ (3 mol % Y₂O₃ in ZrO₂)and 8YSZ (8 mol % Y₂O₃ in ZrO₂), wherein the mass ratio of 3YSZ/8YSZ isin the range of from 10/90 to 90/10 and wherein the DFS is impermeableto non-ionic substances and electrically insulating. In an embodiment,the mass ratio of 3YSZ/8YSZ is about 50/50 or 40/60 or 60/40 or 30/70 or70/30 or 20/80 or 80/20. In an embodiment, the DFS is used as anelectrolyte in a fuel cell or as a portion of a fuel cell casing, orboth.

Further disclosed herein is a method comprising providing a DFS in afuel cell system, wherein the DFS comprises 3YSZ (3 mol % Y₂O₃ in ZrO₂)and 8YSZ (8 mol % Y₂O₃ in ZrO₂), wherein the mass ratio of 3YSZ/8YSZ isin the range of from 100/0 to 0/100 or from 10/90 to 90/10 and whereinthe DFS is impermeable to non-ionic substances and electricallyinsulating. In an embodiment, the mass ratio of 3YSZ/8YSZ is about 50/50or 40/60 or 60/40 or 30/70 or 70/30 or 20/80 or 80/20.

In an embodiment, the DFS is used as electrolyte or a portion of a fuelcell casing or both in the fuel cell system. The portion of a fuel cellcasing may be the entire fuel cell casing. The portion of a fuel cellcasing is a coating on the fuel cell casing. The electrolyte and saidportion of a fuel cell casing are in contact.

Disclosed herein is a fuel cell system comprising an anode having sixsurfaces, a cathode having six surfaces, an electrolyte, and an anodesurround in contact with at least three surfaces of the anode, whereinthe electrolyte is part of the anode surround and said anode surround ismade of the same material as the electrolyte. In an embodiment, saidsame material is a DFS comprising 3YSZ (3 mol % Y₂O₃ in ZrO₂) and 8YSZ(8 mol % Y₂O₃ in ZrO₂), wherein the mass ratio of 3YSZ/8YSZ is in therange of from 100/0 to 0/100 or from 10/90 to 90/10 and wherein the DFSis impermeable to non-ionic substances and electrically insulating. Inan embodiment, the mass ratio of 3YSZ/8YSZ is about 50/50 or 40/60 or60/40 or 30/70 or 70/30 or 20/80 or 80/20. In an embodiment, the anodesurround is in contact with five surfaces of the anode.

In an embodiment, the fuel cell system comprises a barrier layer betweenthe cathode and a cathode surround, wherein the barrier layer is incontact with at least three surfaces of the cathode, wherein theelectrolyte is part of the cathode surround and said cathode surround ismade of the same material as the electrolyte.

In an embodiment, the fuel cell system comprises fuel passage andoxidant passage in the anode surround and the cathode surround. In anembodiment, the fuel cell system comprises an interconnect, wherein theinterconnect comprises no fluid dispersing element and said anode andcathode comprise fluid dispersing components. In an embodiment, the fuelcell system comprises an interconnect, wherein the interconnectcomprises no fluid dispersing element and said anode and cathodecomprise fluid channels.

Tubular Design

In various cases, the electrochemical reactors as discussed in thisdisclosure are tubular. The discussion in this section takes tubularfuel cell (TFC) as an example of a tubular electrochemical reactor. Thetubular design is applicable to other types of electrochemical reactors,e.g., the EC gas producers, the EC compressors, or flow batteries.Herein disclosed is a tubular fuel cell (TFC) comprising an internalcathode, an external anode, an electrolyte placed between the anode andthe cathode, and an interconnect. In some embodiments of a TFC, anelectrolyte is considered as a membrane. The cross section of thecathode is a rounded non-circular shape with no sharp corner, whereinthe cross section is orthogonal to the longitudinal axis of the TFC,wherein said interconnect is in contact with the cathode but not withthe anode and said interconnect has a contacting surface configured tocontact an anode of an adjacent TFC, wherein the anode has a contactingsurface configured to contact an interconnect of another adjacent TFCand a non-contacting surface.

In an embodiment, the TFC comprises a barrier layer between the cathodeand the electrolyte or between the anode and the electrolyte or both. Inan embodiment, the rounded non-circular shape comprises roundedrectangle, rounded square, rounded hexagon, rounded trapezoid, roundedparallelogram, rounded pentagon, rounded triangle, rounded octagon,oval, ellipsoid, or rounded irregular shape or combinations thereof.

In an embodiment, the ratio of the area of the contacting surface of theinterconnect over the area of the non-contacting surface of the anode isno greater than 1, or no greater than 0.75, or no greater than 0.5. Inan embodiment, the ratio of the area of the contacting surface of theinterconnect over the area of the non-contacting surface of the anode isno greater than 0.3, or no greater than 0.1, or no greater than 0.05.

In an embodiment, the thickness of the cathode is in the range of fromabout 10 microns to about 1,000 microns; or from about 50 to about 150microns; or from about 90 to about 110 microns; or about 100 microns. Inan embodiment, the thickness of the anode is in the range of from about1 micron to about 50 microns; or from about 5 microns to about 25microns; or from about 8 microns to about 12 microns; or about 10microns. In an embodiment, the thickness of the electrolyte is in therange of from about 100 nm to about 10 microns; or from about 500 nm toabout 5 microns; or from about 800 nm to about 2 microns; or about 1micron. In an embodiment, the thickness of the barrier layer is in therange of from about 100 nm to about 10 microns; or from about 500 nm toabout 5 microns; or from about 800 nm to about 2 microns; or about 1micron. In an embodiment, the thickness of the interconnect is in therange of from about 10 microns to about 1000 microns; or from about 50microns to about 500 microns; or from about 80 microns to about 200microns; or about 100 microns.

In an embodiment, the TFC has a length L and the cross section has acharacteristic length of W, wherein the ratio of L/W is no less than 1.In an embodiment, the ratio of L/W is no less than 2 or no less than 10or no less than 100.

In an embodiment, the TFC comprises a support in the cathode. In anembodiment, the support is in contact with the cathode. In anembodiment, the support is an integral part of the cathode. In anembodiment, the support and the cathode are made from the same material.In an embodiment, the support and the cathode are made from differentmaterials. In an embodiment, the electrolyte is impermeable to fluids.In an embodiment, the cathode and the anode are porous.

Also discussed herein is a fuel cell stack comprising a multiplicity oftubular fuel cells (TFCs), wherein each of said TFCs comprises aninternal cathode, an external anode, an electrolyte placed between theanode and the cathode, and an interconnect, wherein a cross section ofthe cathode is a rounded non-circular shape with no sharp corner,wherein the cross section is orthogonal to the longitudinal axis of theTFC, wherein said interconnect is in contact with the cathode but notwith the anode and said interconnect has a contacting surface configuredto contact an anode of an adjacent TFC, wherein said anode has acontacting surface configured to contact an interconnect of anotheradjacent TFC and a non-contacting surface.

In an embodiment, each of said TFCs comprises a barrier layer betweenthe cathode and the electrolyte or between the anode and the electrolyteor both. In an embodiment, said rounded non-circular shape comprisesrounded rectangle, rounded square, rounded hexagon, rounded trapezoid,rounded parallelogram, rounded pentagon, rounded triangle, roundedoctagon, oval, ellipsoid, rounded irregular shape.

In an embodiment, the ratio of the area of the contacting surface of theinterconnect over the area of the non-contacting surface of the anode isno greater than 1, or no greater than 0.75, or no greater than 0.5. Inan embodiment, the ratio of the area of the contacting surface of theinterconnect over the area of the non-contacting surface of the anode isno greater than 0.3, or no greater than 0.1, or no greater than 0.05.

In an embodiment, each of said TFCs has a length L and the cross sectionhas a characteristic length of W, wherein the ratio of L/W is no lessthan 1 or no less than 2 or no less than 10 or no less than 100.

In an embodiment, each of said TFCs comprises a support in the cathode.In an embodiment, the support is in contact with the cathode. In anembodiment, the support is an integral part of the cathode. In anembodiment, the support and the cathode are made from the same material.

Herein disclosed is a tubular fuel cell (TFC) comprising an internalanode, an external cathode, an electrolyte placed between the anode andthe cathode, and an interconnect, wherein a cross section of the anodeis a rounded non-circular shape with no sharp corner, wherein the crosssection is orthogonal to the longitudinal axis of the TFC, wherein theinterconnect is in contact with the anode but not with the cathode andthe interconnect has a contacting surface configured to contact acathode of an adjacent TFC, wherein the cathode has a contacting surfaceconfigured to contact an interconnect of another adjacent TFC and anon-contacting surface.

In an embodiment, the rounded non-circular shape comprises roundedrectangle, rounded square, rounded hexagon, rounded trapezoid, roundedparallelogram, rounded pentagon, rounded triangle, rounded octagon,oval, ellipsoid, rounded irregular shape or combination thereof. In anembodiment, the ratio of the area of the contacting surface of theinterconnect over the area of the non-contacting surface of the cathodeis no greater than 1, or no greater than 0.75, or no greater than 0.5,no greater than 0.3, or no greater than 0.1, or no greater than 0.05. Inan embodiment, the TFC comprises a barrier layer between the cathode andthe electrolyte or between the anode and the electrolyte or both.

FIGS. 10A-10C illustrate different aspect ratios of fuel cells and howthat may be connected in multi-tubular fuel cell (TFC) units comprisingtwo or more TFCs. The TFCs comprise rounded edges. FIG. 10A illustratesa cross-sectional view of a TFC 1000, according to an embodiment of thedisclosure. TFC 1000 comprises an internal cathode layer 1002, barrierlayer 1004, electrolyte layer 1006, an external anode layer 1008, aninterconnect 1010 and a fluid passage 1012. In some cases, the barrierlayer 1004 is placed between anode 1008 and electrolyte 1006. In somecases, two barrier layers are placed (1) between cathode 1002 andelectrolyte 1006 and (2) between anode 1008 and electrolyte 1006.Interconnect 1010 is in contact with cathode 1002 but not with anode1008. The top surface of interconnect 1010 is configured to be contactwith the anode 1008 of an adjacent TFC. Anode 1008 has a contactingsurface on the bottom configured to be in contact with interconnect 1010of another adjacent TFC. Anode 1008 has a non-contacting surface on bothsides in the configuration as shown in FIGS. 10A-10C. In this example inFIG. 10A, the TFCs 1000 have a rounded rectangular shape that areconnected by interconnects 1010 on the short end of the rectangularshape.

FIG. 10B illustrates a cross-sectional view of a TFC 1020, according toan embodiment of the disclosure. TFCs 1020 are similar in constructionto TFCs 1000 but are connected by interconnects 1010 on the long side ofthe rectangular shape.

FIG. 10C illustrates a cross-sectional view of a TFC 1040, according toan embodiment of the disclosure. TFCs 1040 in FIG. 10C are similar inconstruction to TFCs in FIGS. 10A-10B but comprise a rounded square-likeshape wherein the length of the sides are substantially the same. TheTFCs 1040 are further connected by interconnects 1010.

In alternative embodiments, the anode 1008 may be configured to beinternal and the cathode 1002 may be external. In some cases, thebarrier layer may be placed between cathode and electrolyte. In somecases, two barrier layers are placed (1) between cathode and electrolyteand (2) between anode and electrolyte. All the other configurations andfeatures as discussed above are applicable in this embodiment as well.

In some embodiment, the TFC may further comprise one or more supports inthe cathode layer as shown in FIGS. 11A-11C. FIG. 11A illustrates across-sectional view of a TFC 1100 comprising a support, according to anembodiment of the disclosure. TFC 1100 comprises a cathode 1002, barrierlayer 1004, electrolyte 1006, anode layer 1008, interconnect 1010 and atleast one fluid passage 1012. The shape and design of how the TFCs 1100are arranged is similar to TFCs in FIG. 10A. TFCs 1100 further compriseone or more supports. The supports may be in any shape, number, size,and material as suitable. In some cases, the supports 1102 are made fromthe same material as the internal electrode layer such as cathode layer1002. In some cases, the supports 1104 are made from a materialdifferent from the internal electrode layer such as cathode 1002material. For example, an inert material in relation to the fuel cell.In some cases, the supports may be made from more than one material. Inan embodiment, the one or more supports 1102, 1104 are in contact withthe cathode 1002. In an embodiment, the one or more supports 1102, 1104are integral parts of the cathode. In an embodiment, the one or moresupports 1102, 1104 are made as an integral part of the cathode.

FIG. 11B illustrates a cross-sectional view of a TFC 1120 comprising asupport, according to an embodiment of the disclosure. The shape anddesign of how the TFCs 1120 are arranged is similar to TFCs in FIG. 10B.TFCs 1120 further comprise one or more supports. The support 1102 may bea linear shaped support of the same material as the inner electrode suchas the cathode 1002. The support 1104 may be a linear shaped support1104 not constructed of the same material. The support 1106 may be anoval or circular-like shaped support constructed of the same material asthe inner electrode, such as cathode 1002. The support 1108 may be anoval or circular-like shaped support not constructed of the samematerial as the inner electrode, such as cathode 1002. As seen in FIG.11B, TFCs may comprise linear shaped supports 1102, 1104 andcircular-shaped supports 1106, 1108.

FIG. 11C illustrates a cross-sectional view of a TFC 1140 comprising asupport, according to an embodiment of the disclosure. The shape anddesign of how the TFCs 1140 are arranged is similar to TFCs in FIG. 10C.TFCs 1140 further comprise one or more supports. In this example, all ofthe supports 1106, 1108 may be circular-like or oval-like shaped thoughlinear shaped supports 1102, 1104 may also be used.

In some embodiments, the inner electrode may be an anode layer 1008 inTFCs 1100, 1120, 1140. The supports 1102, 1104, 1106, 1108 may beconstructed of the same material of the inner anode layer or notconstructed of the anode layer 1008 or a combination thereof.

Herein discussed is a method comprising placing a fluidic mixturebetween two tubular fuel cells (TFCs), wherein said two TFCs have a gapwith a minimum distance of no greater than 1 mm; heating the fluidicmixture such that the two TFCs are connected; wherein the fluidicmixture has a viscosity of no greater than 1000 centipoise. In anembodiment, the fluidic mixture has a viscosity of no greater than 500centipoise or no greater than 300 centipoise or no greater than 200centipoise or no greater than 100 centipoise or no greater than 50centipoises. In an embodiment, the minimum distance of the gap is nogreater than 500 microns, or no greater than 300 microns, or no greaterthan 200 microns, or no greater than 100 microns, or no greater than 50microns.

In an embodiment, placing the fluidic mixture comprises aerosol jetting,material jetting, ink jet printing or combinations thereof. In anembodiment, the fluidic mixture comprises a fluid and a solid andwherein heating the fluidic mixture causes the fluid to dissipate andthe solid to remain. In an embodiment, heating the fluidic mixturecauses it to solidify. In an embodiment, the heating comprises the useof electromagnetic radiation (EMR). In an embodiment, EMR comprises UVlight, near ultraviolet light, near infrared light, infrared light,visible light, laser, electron beam, microwave, or combinations thereof.In an embodiment, the heating comprising oven heating, furnace heating,kiln heating, plasma heating, hot surface heating, or combinationsthereof. In an embodiment, the heating is accomplished via conduction,convection, radiation, or combinations thereof. In an embodiment, saidheating causes sintering, co-sintering, annealing, densification,solidification, evaporation, drying, or combinations thereof.

In an embodiment, the fluidic mixture comprises gold, silver, platinum,nickel, iron, steel, stainless steel, chromium, cobalt, carbon, orinconel. In an embodiment, the fluidic mixture comprises material usedfor an electrode in the fuel cells or material used for an interconnectin the fuel cells or both.

In an embodiment, each of the TFCs comprises an internal cathode, anexternal anode, an electrolyte placed between the anode and the cathode,and an interconnect, wherein a cross section of the cathode is a roundednon-circular shape with no sharp corner, wherein the cross section isorthogonal to the longitudinal axis of the TFC, wherein the interconnectis in contact with the cathode but not with the anode and saidinterconnect has a contacting surface configured to contact an anode ofan adjacent TFC, wherein said anode has a contacting surface configuredto contact an interconnect of another adjacent TFC and a non-contactingsurface.

In an embodiment, each of the TFCs comprises an internal anode, anexternal cathode, an electrolyte placed between the anode and thecathode, and an interconnect, wherein a cross section of the anode is arounded non-circular shape with no sharp corner, wherein the crosssection is orthogonal to the longitudinal axis of the TFC, wherein theinterconnect is in contact with the anode but not with the cathode andsaid interconnect has a contacting surface configured to contact acathode of an adjacent TFC, wherein the cathode has a contacting surfaceconfigured to contact an interconnect of another adjacent TFC and anon-contacting surface.

Also discussed herein is a method comprising applying contact paste on afirst tubular fuel cell (TFC) and placing a second TFC in contact withthe contact paste on the opposite side of the first TFC, wherein each ofthe first TFC and second TFC comprises an internal cathode, an externalanode, an electrolyte placed between the anode and the cathode, and aninterconnect, wherein a cross section of the cathode is a roundednon-circular shape with no sharp corner, wherein the cross section isorthogonal to the longitudinal axis of the TFC, wherein the interconnectis in contact with the cathode but not with the anode and saidinterconnect has a contacting surface configured to contact an anode ofan adjacent TFC, wherein the anode has a contacting surface configuredto contact an interconnect of another adjacent TFC and a non-contactingsurface.

In an embodiment, the contact paste is applied via dipping, coating,spreading, spraying, airbrushing, spray pyrolysis, or painting orcombinations thereof. In an embodiment, the contact paste comprisesgold, silver, platinum, nickel, iron, steel, stainless steel, chromium,cobalt, carbon, or Inconel or combinations thereof. In an embodiment,the contact paste comprises material used for an electrode in the fuelcells or material used for an interconnect in the fuel cells or both. Inan embodiment, the TFC comprises a barrier layer between the cathode andthe electrolyte or between the anode and the electrolyte or both.

In an embodiment, the rounded non-circular shape comprises roundedrectangle, rounded square, rounded hexagon, rounded trapezoid, roundedparallelogram, rounded pentagon, rounded triangle, rounded octagon,oval, ellipsoid, or rounded irregular shape. In an embodiment, the ratioof the area of the contacting surface of the interconnect over the areaof the non-contacting surface of the anode is no greater than 1, or nogreater than 0.75, or no greater than 0.5. In an embodiment, the ratioof the area of the contacting surface of the interconnect over the areaof the non-contacting surface of the anode is no greater than 0.3, or nogreater than 0.1, or no greater than 0.05. In an embodiment, the TFC hasa length L and wherein the cross section has a characteristic length ofW, wherein the ratio of L/W is no less than 1, or no less than 2 or noless than 10 or no less than 100.

In an embodiment, the TFC comprises a support in the cathode. In anembodiment, the support is in contact with the cathode. In anembodiment, the support is an integral part of the cathode. In anembodiment, the support and the cathode are made from the same material.

In an embodiment, the method comprises heating the contact paste. In anembodiment, the heating comprises the use of electromagnetic radiation(EMR). In an embodiment, EMR comprises UV light, near ultraviolet light,near infrared light, infrared light, visible light, laser, electron beamor combinations thereof. In an embodiment, the heating comprising ovenheating, furnace heating, kiln heating, plasma heating, hot surfaceheating, or combinations thereof. In an embodiment, said heating isaccomplished via conduction, convection, radiation, or combinationsthereof. In an embodiment, said heating causes sintering, co-sintering,annealing, densification, solidification, evaporation, drying, orcombinations thereof.

Further discussed herein is a method comprising applying contact pasteon a first tubular fuel cell (TFC) and placing a second TFC in contactwith the contact paste on the opposite side of the first TFC, whereineach of the first TFC and second TFC comprises an internal anode, anexternal cathode, an electrolyte placed between the anode and thecathode, and an interconnect, wherein a cross section of the anode is arounded non-circular shape with no sharp corner, wherein the crosssection is orthogonal to the longitudinal axis of the TFC, wherein saidinterconnect is in contact with the anode but not with the cathode andsaid interconnect has a contacting surface configured to contact acathode of an adjacent TFC, wherein said cathode has a contactingsurface configured to contact an interconnect of another adjacent TFCand a non-contacting surface.

In an embodiment, the contact paste is applied via dipping, coating,spreading, spraying, painting, or combinations thereof. In anembodiment, the contact paste comprises gold, silver, platinum, nickel,iron, steel, stainless steel, chromium, cobalt, carbon, or Inconel orcombinations thereof. In an embodiment, the contact paste comprisesmaterial used for an electrode in the fuel cells or material used for aninterconnect in the fuel cells or both. In an embodiment, the TFCcomprises a barrier layer between the cathode and the electrolyte orbetween the anode and the electrolyte or both. In an embodiment, theratio of the area of the contacting surface of the interconnect over thearea of the non-contacting surface of the anode is no greater than 1, orno greater than 0.75, or no greater than 0.5, or no greater than 0.3, orno greater than 0.1, or no greater than 0.05. In an embodiment, the TFChas a length L and wherein the cross section has a characteristic lengthof W, wherein the ratio of L/W is no less than 1, or no less than 2 orno less than 10 or no less than 100.

In an embodiment, the TFC comprises a support in the anode. In anembodiment, the support is in contact with the anode. In an embodiment,the support is an integral part of the anode. In an embodiment, thesupport and the anode are made from the same material.

In an embodiment, the method comprises heating the contact paste. In anembodiment, the heating comprises the use of electromagnetic radiation(EMR). In an embodiment, EMR comprises UV light, near ultraviolet light,near infrared light, infrared light, visible light, laser, electronbeam, microwave. In an embodiment, said heating comprising oven heating,furnace heating, kiln heating, plasma heating, hot surface heating, orcombinations thereof. In an embodiment, the heating is accomplished viaconduction, convection, radiation, or combinations thereof. In anembodiment, said heating causes sintering, co-sintering, annealing,densification, solidification, evaporation, drying, or combinationsthereof.

Integrated Heat Exchanger

Disclosed herein is an electrochemical (EC) reactor, such as a EC gasproducer or a solid oxide reactor (SOR), comprising a first electrode, asecond electrode, an electrolyte between the first and secondelectrodes, and a first heat exchanger, wherein the first heat exchangeris in fluid communication with the first electrode. The minimum distancebetween the first electrode and the first heat exchanger is no greaterthan 10 cm. In some embodiments, the minimum distance is no greater than5 cm. In other embodiments, the minimum distance is no greater than 1cm. In still other embodiments, the minimum distance is no greater than5 mm. In even still other embodiments, the minimum distance is nogreater than 1 mm. In an embodiment, the EC reactor comprises a secondheat exchanger, wherein the second heat exchanger is in fluidcommunication with the second electrode. The minimum distance betweenthe second electrode and the second heat exchanger no greater than 10cm. In some embodiments, the minimum distance is no greater than 5 cm.In other embodiments, the minimum distance is no greater than 1 cm. Instill other embodiments, the minimum distance is no greater than 5 mm.In even still other embodiments, the minimum distance is no greater than1 mm.

In one embodiment, the first heat exchanger is adjacent to the firstelectrode, or alternatively wherein the second heat exchanger isside-by-side or adjacent to the second electrode. The one or more heatexchangers may be placed side-by-side the components in an EC reactor,or on top of or below the components (i.e., electrodes) of an ECreactor. FIG. 9B is an illustrative example where an integratedmulti-fluid heat exchanger comprising 916 and 918 is at the bottom of arepeat unit/stack in a fuel cell separated only by an interconnect layer920 from the anode 910. In this case, the minimum distance between theheat exchanger and the repeat unit/stack is only the thickness of theinterconnect, which is 1 mm or less, 0.5 mm or less, 200 microns orless, or in the range of about 100 nm to about 100 microns. In someembodiments, the first heat exchanger and the second heat exchanger arethe same heat exchanger, wherein the heat exchangers form a multi-fluidheat exchanger. The EC reactor may comprise a solid oxide fuel cell,solid oxide flow battery, electrochemical gas producer, orelectrochemical compressor. The EC reactor may comprise a reformerupstream of the first electrode or a reformer in contact with the firstelectrode or a reformer in the first heat exchanger. The EC reactor maycomprise two or more repeat units separated by interconnects, whereineach repeat unit comprises a first electrode, a second electrode, and anelectrolyte. Each repeat unit may comprise at least one heat exchangeradjacent to the repeat unit.

Herein also disclosed is an EC reactor, such as a solid oxide reactor(SOR), comprising a stack and a heat exchanger. The stack has a stackheight and comprises multiple repeat units separated by interconnects,wherein each repeat unit comprises a first electrode, a secondelectrode, and an electrolyte between the first and second electrodes.The heat exchanger is in fluid communication with the stack and whereinthe minimum distance between the stack and the heat exchanger is nogreater than 2 times the stack height, or no greater than the stackheight, or no greater than half the stack height. The heat exchanger maybe adjacent to the stack. The heat exchanger comprises at least threefluid inlets and at least three fluid channels, wherein each of the atleast three fluid channels has a minimum dimension of no greater than 30mm. The stack or the heat exchanger may further comprise a reformer. Thereformer may be built into the stack or the heat exchanger. In anembodiment, the interconnect comprises no fluid dispersing element andthe electrodes comprise fluid dispersing components or fluid channels.

In an embodiment, the EC reactor is in the form of a cartridge (such asthat illustrated in FIGS. 9A-9D). The cartridge may comprise a fuelentrance on a fuel side of the cartridge, an oxidant entrance on anoxidant side of the cartridge, at least one fluid exit, wherein the fuelentrance has a width of W_(f), the fuel side of the cartridge has alength of L_(f), the oxidant entrance has a width of W_(o), the oxidantside of the cartridge has a length of L_(o), wherein W_(f)/L_(f) is inthe range of 0.1 to 1.0, 0.1 to 0.9, 0.2 to 0.9, 0.5 to 0.9, or 0.5 to1.0 and W_(o)/L_(o) is in the range of 0.1 to 1.0, 0.1 to 0.9, 0.2 to0.9, 0.5 to 0.9, or 0.5 to 1.0. In some embodiments, the entrances andexit are on one surface of the cartridge wherein the cartridge comprisesno protruding fluid passage on the surface. The cartridge may bedetachably fixed to a mating surface and not soldered nor welded to themating surface. The cartridge may be bolted to or pressed to the matingsurface. The mating surface may comprise a matching fuel entrance,matching oxidant entrance, and at least one matching fluid exit.

Further disclosed herein is a EC reactor cartridge, such as a solidoxide reactor cartridge (SDRC), comprising a first electrode, a secondelectrode, an electrolyte between the first and second electrodes, and aheat exchanger, wherein said heat exchanger is in fluid communicationwith the first electrode or the second electrode or both. The minimumdistance between the heat exchanger and the first electrode or thesecond electrode is no greater than 10 cm, or no greater than 5 cm, orno greater than 1 cm, or no greater than 5 mm, or no greater than 1 mm.

In an embodiment, the EC reactor cartridge comprises a reformer upstreamof the first electrode or a reformer in contact with the first electrodeor a reformer in the heat exchanger. The EC reactor cartridge maycomprise a fuel entrance on a fuel side of the cartridge, an oxidantentrance on an oxidant side of the cartridge, at least one fluid exit,wherein the fuel entrance has a width of W_(f), the fuel side of thecartridge has a length of L_(f), the oxidant entrance has a width ofW_(o), the oxidant side of the cartridge has a length of L_(o). Theratio of W_(f)/L_(f) is in the range of 0.1 to 1.0, 0.1 to 0.9, 0.2 to0.9, 0.5 to 0.9, or 0.5 to 1.0 and the ratio of W_(o)/L_(o) is in therange of 0.1 to 1.0, 0.1 to 0.9, 0.2 to 0.9, 0.5 to 0.9, or 0.5 to 1.0.The entrances and exit may be on one surface of the cartridge andwherein the cartridge comprises no protruding fluid passage on thesurface. The EC reactor cartridge may be detachably fixed to a matingsurface and not soldered nor welded to the mating surface.

Discussed herein is a method of forming an EC reactor, such as a solidoxide reactor (SOR), comprising forming a first electrode in a device,forming an electrolyte in the same device, forming a second electrode inthe same device, and forming a heat exchanger in the same device,wherein the electrolyte is between the first electrode and the secondelectrode and is in contact with the electrodes. The heat exchanger maybe in fluid communication with the first electrode or the secondelectrode or both. The forming method may comprise one or more ofmaterial jetting, binder jetting, inkjet printing, aerosol jetting,aerosol jet printing, vat photopolymerization, powder bed fusion,material extrusion, directed energy deposition, sheet lamination,ultrasonic inkjet printing, direct (dry) powder deposition, orcombinations thereof. Preferably, the forming is accomplished by inkjetprinting.

In an embodiment, the method of forming an EC reactor further comprisesheating the EC reactor. The heating may be performed in situ. Theheating may be performed using electromagnetic radiation (EMR). Themethod of forming an EC reactor may further comprise forming multiplerepeat units and interconnects between the repeat units, wherein arepeat unit comprises the first electrode, the electrolyte, and thesecond electrode. In an embodiment, forming the repeat units and theinterconnects take place in the same device. In a preferred embodiment,the method comprises heating the repeat units and the interconnects insitu using EMR. In a preferred embodiment, the method further comprisesforming a reformer. The reformer may be formed in the same device.

In an embodiment, the interconnects in the EC reactor comprise no fluiddispersing element. In an embodiment, the method of forming an ECreactor comprises forming a first template while forming the firstelectrode, wherein the first template is in contact with the firstelectrode; removing at least a portion of the first template to formchannels in the first electrode. The method further comprises forming asecond template while forming the second electrode, wherein the secondtemplate is in contact with the second electrode; removing at least aportion of the second template to form channels in the second electrode.In an embodiment, the first electrode comprises fluid dispersingcomponents (FDC) or fluid channels; wherein the second electrodecomprises fluid dispersing components (FDC) or fluid channels.

In an embodiment, the EC reactor, such as an SOR, is formed into acartridge. The cartridge comprises a fuel entrance on a fuel side of thecartridge, an oxidant entrance on an oxidant side of the cartridge, atleast one fluid exit, wherein the fuel entrance has a width of W_(f),the fuel side of the cartridge has a length of L_(f), the oxidantentrance has a width of W_(o), and the oxidant side of the cartridge hasa length of L_(o). The ratio of W_(f)/L_(f) may be in the range of 0.1to 1.0, 0.1 to 0.9, 0.2 to 0.9, 0.5 to 0.9, or 0.5 to 1.0 and the ratioof W_(o)/L_(o) is in the range of 0.1 to 1.0, 0.1 to 0.9, 0.2 to 0.9,0.5 to 0.9, or 0.5 to 1.0. In an embodiment, the entrances and exit areon one surface of the cartridge and said cartridge comprises noprotruding fluid passage on said surface. In an embodiment, thecartridge is detachably fixed to a mating surface and not soldered norwelded to the mating surface. The cartridge may be bolted to or pressedto the mating surface. In an embodiment, the method comprises forming areformer upstream of the first electrode or a reformer in contact withthe first electrode or a reformer in the heat exchanger. The reformermay be formed in the same device.

Also disclosed herein is a method comprising forming an EC reactor stackand a heat exchanger, wherein the stack having a stack height comprisesmultiple repeat units separated by interconnects, wherein each repeatunit comprises a first electrode, a second electrode, and an electrolytebetween the first and second electrodes. The heat exchanger may be influid communication with the stack and wherein the minimum distancebetween the stack and the heat exchanger is no greater than 2 times thestack height, or no greater than the stack height, or no greater thanhalf the stack height.

In an embodiment, the EC reactor stack, such as an SOR, and the heatexchanger are formed in the same device. The method may comprise formingthe stack and the heat exchanger into a cartridge. The cartridge may bedetachably fixed to a mating surface and not soldered nor welded to themating surface.

Further discussed herein is a method comprising forming an EC reactor,such as a SOR, comprising a first electrode, a second electrode, anelectrolyte between the first and second electrodes, and a heatexchanger. The heat exchanger may be in fluid communication with thefirst electrode or the second electrode or both. The minimum distancebetween the heat exchanger and the first electrode or the secondelectrode is no greater than 10 cm, no greater than 5 cm, no greaterthan 1 cm, no greater than 5 mm, or no greater than 1 mm. In some cases,the electrodes, the electrolyte, and the heat exchanger are formed inthe same device. The method in some cases also comprises forming the ECreactor into a cartridge. The cartridge may be detachably fixed to amating surface and not soldered nor welded to the mating surface.

Disclosed herein is a method comprising forming an EC reactor cartridgecomprising forming a first electrode, forming a second electrode,forming an electrolyte between the first and second electrodes, andforming a heat exchanger. In an embodiment, the heat exchanger is influid communication with the first electrode or the second electrode orboth. In an embodiment, the electrodes, the electrolyte, and the heatexchanger are formed in the same device. In an embodiment, the methodcomprises forming a reformer upstream of the first electrode or areformer in contact with the first electrode or a reformer in the heatexchanger. In an embodiment, the reformer is formed in the same device.

Fischer Tropsch

The method and system of this disclosure are suitable for making acatalyst or a catalyst composite, such as a Fischer-Tropsch (FT)catalyst or catalyst composite. Disclosed herein is a Fischer-Tropsch(FT) catalyst composite comprising a catalyst and a substrate, whereinthe mass ratio between the catalyst and the substrate is in no less than1/100, or no less than 1/10, or no less than 1/5, or no less than 1/3,or no less than 1/1. In an embodiment, the catalyst comprises Fe, Co,Ni, or Ru. The substrate comprises Al₂O₃, ZrO₂, SiO₂, TiO₂, CeO₂,modified Al₂O₃, modified ZrO₂, modified SiO₂, modified TiO₂, modifiedCeO₂, gadolinium, steel, cordierite (2MgO-2Al₂O₃-5SiO₂), aluminumtitanate (Al₂TiO₅), silicon carbide (SiC), all phases of aluminum oxide,yttria or scandia-stabilized zirconia (YSZ), gadolinia or samaria-dopedceria, or combinations thereof. In an embodiment, the catalyst compositecomprises a promoter wherein the promoter comprises noble metals, metalcations, or combinations thereof. The promoter may comprise B, La, Zr,K, Cu, or combinations thereof. In an embodiment, the catalyst compositecomprises fluid channels or alternatively fluid dispersing components.

The FT reactor/system of this disclosure is much smaller thantraditional FT reactors/systems (e.g., 3-100 times smaller or 100+ timessmaller for the same FT product generation rate). The high catalyst tosubstrate ratio is not achievable by traditional methods to make FTcatalysts. As such, in some embodiments, the FT reactor system isminiaturized compared to traditional FT reactors/systems.

Also discussed herein is a method comprising depositing a FT catalyst toa substrate to form a FT catalyst composite, wherein said depositingcomprises material jetting, binder jetting, inkjet printing, aerosoljetting, or aerosol jet printing, vat photopolymerization, powder bedfusion, material extrusion, directed energy deposition, sheetlamination, ultrasonic inkjet printing, or combinations thereof. In anembodiment, the mass ratio between the catalyst and the substrate is inno less than 1/100, or no less than 1/10, or no less than 1/5, or noless than 1/3, or no less than 1/1. In preferred embodiments, thedeposition method comprises forming fluid channels or alternativelyfluid dispersing components in the catalyst composite.

Further discussed herein is a system comprising a Fischer-Tropsch (FT)reactor containing a FT catalyst composite comprising a catalyst and asubstrate, wherein the mass ratio between the catalyst and the substrateis in no less than 1/100, or no less than 1/10, or no less than 1/5, orno less than 1/3, or no less than 1/1. In an embodiment, the catalystcomprises Fe, Co, Ni, or Ru. In an embodiment, the substrate comprisesAl₂O₃, ZrO₂, SiO₂, TiO₂, CeO₂, modified Al₂O₃, modified ZrO₂, modifiedSiO₂, modified TiO₂, modified CeO₂, gadolinium, steel, cordierite(2MgO-2Al₂O₃-5SiO₂), aluminum titanate (Al₂TiO₅), silicon carbide (SiC),all phases of aluminum oxide, yttria or scandia-stabilized zirconia(YSZ), gadolinia or samaria-doped ceria, or combinations thereof. In anembodiment, the catalyst composite comprises a promoter.

As an example, a FT catalyst composite is formed via printing. Thecatalyst and the substrate/support are made into an ink form comprisinga solvent and particles (e.g., nanoparticles). The ink optionallycomprises a dispersant, a binder, a plasticizer, a surfactant, aco-solvent, or combinations thereof. The ink may be any kind ofsuspension. The ink may be treated with a mixing process, such asultrasonication or high shear mixing. In some cases, an iron ink is inan aqueous environment. In some cases, an iron ink is in an organicenvironment. The iron ink may also include a promoter. Thesubstrate/support may be a suspension or ink of alumina, in an aqueousenvironment or an organic environment. The substrate ink may be treatedwith a mixing process, such as ultrasonication or high shear mixing. Insome cases, the substrate ink comprises a promoter. In some cases, thepromoter is added as its own ink, in an aqueous environment or anorganic environment. In some cases, the various inks are printedseparately and sequentially. In some cases, the various inks are printedseparately and simultaneously, for example, through different printheads. In some cases, the various inks are printed in combination as amixture.

As an example, an exhaust from the fuel cell comprises hydrogen, carbondioxide, water, and optionally carbon monoxide. The exhaust is passedover a FT catalyst (e.g., an iron catalyst) to produce synthetic fuelsor lubricants. The FT iron catalyst has the property to promote watergas shift reaction or reverse water gas shift reaction. The FT reactionstake place at a temperature in the range of 150-350° C. and a pressurein the range of one to several tens of atmospheres (e.g., 15 atm or 10atm or 5 atm or 1 atm). Additional hydrogen may be added to the exhauststream to reach a hydrogen to carbon oxides ratio (carbon dioxide andcarbon monoxide) of no less than 2 or no less than 3 or between 2 and 3.

Fluid Dispersing Component

FIG. 12A illustrates an impermeable interconnect 1202 with a fluiddispersing component 1204, according to an embodiment of the disclosure.FIG. 12B illustrates an impermeable interconnect 1202 with two fluiddispersing components 1204, according to an embodiment of thedisclosure. The fluid dispersing components 1204 are in contact withboth sides (major faces) of interconnect 1202. As such, the interconnectis shared between two repeat units in an electrochemical reactor, suchas in a EC gas producer. Fluid dispersing components 1204 function todistribute fluids, e.g., reactive gases (such as methane, hydrogen,carbon monoxide, air, oxygen, etc.), in an electrochemical reactor. Assuch, traditional interconnects with channels are no longer needed. Thedesign and manufacturing of such traditional interconnects with channelsis complex and expensive. According to this disclosure, theinterconnects are simply impermeable layers that conduct or collectelectrons, having no fluid dispersing elements.

FIGS. 12C-F schematically illustrate segmented fluid dispersingcomponents 1204 on top of impermeable interconnect 1202, according toembodiments of the disclosure. Such segments may have differentcompositions, shapes, densities, porosities, pore sizes, pore shapes,permeabilities, or combinations thereof. The segments may bediscontinuous. FIG. 13C illustrates segmented fluid dispersingcomponents 1204 of similar shapes but different sizes on an impermeableinterconnect 1202. FIG. 13D illustrates segmented fluid dispersingcomponents 1204 of similar shapes and similar sizes on an impermeableinterconnect 1202, according to an embodiment of the disclosure. FIG.12E illustrates segmented fluid dispersing components 1204 of similarshapes and similar sizes but closely packed on an impermeableinterconnect 1202, according to an embodiment of the disclosure. FIG.12F illustrates segmented fluid dispersing components 1204 of differentshapes and different sizes on an impermeable interconnect 1202,according to an embodiment of the disclosure. It is also contemplatedthat these segments have different compositions, densities, porosities,pore sizes, pore shapes, permeabilities, or combinations thereof.

FIGS. 12G-I schematically illustrates an impermeable interconnect 1202with fluid dispersing component 1204, according to embodiments of thedisclosure. Further illustrated are different fluid inlet and outdesigns. The fluid dispersing components may have varying density,porosity, pore size, pore shape, composition, or permeability, orcombinations thereof, in different portions (e.g., in the lateraldirection or perpendicular to the lateral direction). Such variabilitiesprovide control and adjustability of the fluid flow in the fluiddispersing component. FIG. 12G illustrates an impermeable interconnect1202 and fluid dispersing component 1204, according to an embodiment ofthe disclosure. FIG. 12H illustrates an impermeable interconnect 1202and fluid dispersing component 1204, according to an embodiment of thedisclosure. FIG. 12I illustrates an impermeable interconnect 1202 andfluid dispersing component 1204, according to an embodiment of thedisclosure. 1206 and 1208 in FIGS. 12G-I represent different inlet andoutlet designs, according to embodiments of the disclosure. Theinterconnect 1202 has matching inlet and outlet for each configuration.In FIG. 12I, 1206 represents a fluid inlet and 1208 represents a fluidoutlet. The fluid flow is denoted by arrows 1210. FIG. 12J illustratesan impermeable interconnect 1202 and a fluid dispersing component 1204,according to an embodiment of the disclosure. Further illustrated inFIG. 12J are alternative fluid flow designs as shown by the arrows. Forexample, the fluid may flow from left to right across the fluiddispersing component; or the fluid may flow from front to back acrossthe fluid dispersing component.

FIG. 12K illustrates a fluid dispersing component 1204, according to anembodiment of the disclosure. Fluid dispersing component 1204 designcomprises four corners labeled A, B, C, and D. Location A comprisesfluid flow inlet 1212. Location B comprises fluid flow outlet 1214.

Discussed herein is an electrochemical reactor (e.g., a fuel cell)comprising an impermeable interconnect having no fluid dispersingelement, an electrolyte, a fluid dispersing component (FDC) between theinterconnect and the electrolyte. In an embodiment, the fuel cellcomprises two FDC's. The two FDC's may be symmetrically placed incontact with the interconnect on its opposing side or opposing majorfaces. As such, the interconnect is shared between the two repeat unitsin the electrochemical reactor, each repeat unit comprising one of thetwo FDC's. The FDC may be a foam, open cell foam, or comprises a latticestructure.

In a preferred embodiment, the FDC is segmented wherein the segmentshave different compositions, materials, shapes, sizes, densities,porosities, pore sizes, pore shapes, permeabilities, or combinationsthereof. The shapes of the segments may comprise pillar, hollowcylinder, cube, rectangular cuboid, trigonal trapezohedron,quadrilateral frustum, parallelepiped, triangular bipyramid, tetragonalanti-wedge, pyramid, pentagonal pyramid, prism, or combinations thereof.

In some embodiments, the FDC has varying density, porosity, pore size,pore shape, permeability, or combinations thereof wherein the density,porosity, pore size, pore shape, or permeability or combination thereofis controlled. In some embodiments, the density, porosity, pore size,pore shape, or permeability or combination thereof, is controlled toadjust flow of a fluid through the FDC. In other embodiments, thedensity, porosity, pore size, pore shape, or permeability or combinationthereof is controlled to cause uniform fluid flow from a first point inthe FDC to a second point in the FDC. The fluid flow pattern may beadjusted as desired. For example, it does not need to be uniform. Thefluid flow may be increased or decreased according to the reactivitiesof the FDC or reaction rates of the fluid in the various portions of theFDC. Alternatively and/or in combination, the fluid flow may beincreased or decreased according to the fluid flow rates to an anode ora cathode in the various portions of the FDC. Alternatively and/or incombination, the fluid flow may be increased or decreased according tothe reaction rates in an anode or a cathode related to or in contactwith the various portions of the FDC.

In an embodiment, density is higher in the center of the FDC. In anembodiment, density is lower in the center of the FDC. In an embodiment,porosity or permeability or pore throat size is lower toward the centerof the FDC. In an embodiment, porosity or permeability or pore throatsize is higher toward the center of the FDC.

In an embodiment, at least a portion of the FDC is part of an anode orpart of a cathode. In a preferred embodiment, the FDC is an anode or acathode. In an embodiment, the impermeable interconnect has a thicknessof no greater than 10 microns, or no greater than 1 micron, or nogreater than 500 nm. In a preferred embodiment, the impermeableinterconnect comprises inlets and outlets for fluids. In a preferredembodiment, the fluids comprise reactants for the fuel cell.

Herein also disclosed is a method of making a fuel cell comprising (a)forming an impermeable interconnect having no fluid dispersing element;(b) forming an electrolyte; (c) forming a fluid dispersing component(FDC); and (d) placing the FDC between the interconnect and theelectrolyte.

In an embodiment, the FDC is formed by creating a multiplicity ofsegments and assembling the segments. The segments have differentcompositions, materials, shapes, sizes, densities, porosities, poresizes, pore shapes, permeabilities, or combinations thereof wherein theshapes comprise a pillar, hollow cylinder, cube, rectangular cuboid,trigonal trapezohedron, quadrilateral frustum, parallelepiped,triangular bipyramid, tetragonal anti-wedge, pyramid, pentagonalpyramid, prism, or combinations thereof. The FDC may be a foam, opencell foam; or comprises a lattice structure.

In preferred embodiments, the method of forming the FDC comprisesvarying density, porosity, pore size, pore shape, permeability, orcombinations thereof. In an embodiment, the method comprises controllingthe density, porosity, pore size, pore shape, permeability, orcombinations thereof of the FDC. The method may comprise controllingdensity, porosity, pore size, pore shape, permeability, or combinationsthereof of the FDC to adjust flow of a fluid through the FDC. The methodmay comprise controlling density, porosity, pore size, pore shape,permeability, or combinations thereof of the FDC to cause uniform fluidflow from a first point in the FDC to a second point in the FDC. Themethod may comprise controlling density, porosity, pore size, poreshape, permeability, or combinations thereof of the FDC to causepatterned fluid flow from a first point in the FDC to a second point inthe FDC.

The fluid flow pattern may be adjusted as desired. For example, it doesnot need to be uniform. The fluid flow may be increased or decreasedaccording to the reactivities of the FDC or reaction rates of the fluidin the various portions of the FDC. Alternatively and/or in combination,the fluid flow may be increased or decreased according to the fluid flowrates to an anode or a cathode in the various portions of the FDC.Alternatively and/or in combination, the fluid flow may be increased ordecreased according to the reaction rates in an anode or a cathoderelated to or in contact with the various portions of the FDC.

In an embodiment, step (c) comprises varying composition of materialused to form the FDC. In an embodiment, step (c) comprises varyingparticles size used to form the FDC. In an embodiment, step (c)comprises heating different portions of the FDC to differenttemperatures. In an embodiment, said heating comprises electromagneticradiation (EMR). In an embodiment, EMR comprises one or more of UVlight, near ultraviolet light, near infrared light, infrared light,visible light, laser or electron beam.

In an embodiment, steps (a)-(d) or steps (b)-(d) are performed usingadditive manufacturing (AM). In various embodiments, AM comprisesextrusion, photopolymerization, powder bed fusion, material jetting,binder jetting, directed energy deposition or lamination or combinationsthereof.

In an embodiment, the method of forming the FDCs comprises heating thefuel cell such that shrinkage rates of the FDC and the electrolyte arematched or such that shrinkage rates of the interconnect, the FDC, andthe electrolyte are matched. In a preferred embodiment, the heatingcomprises EMR. In an embodiment, EMR comprises UV light, nearultraviolet light, near infrared light, infrared light, visible light,laser or electron beam or combinations thereof. In a preferredembodiment, heating is performed in situ. In preferred embodiments,heating takes place for no greater than 30 minutes, or no greater than30 seconds, or no greater than 30 milliseconds.

In a preferred embodiment, at least a portion of the FDC is part of ananode or part of a cathode. In a preferred embodiment, the FDC is ananode or a cathode. In preferred embodiments, the impermeableinterconnect has a thickness of no greater than 10 microns, or nogreater than 1 micron, or no greater than 500 nm. Preferably, theimpermeable interconnect comprises inlets and outlets for fluids. Morepreferably, the fluids comprise reactants for the fuel cell.

Channeled Electrodes

Disclosed herein is a method comprising providing a template wherein thetemplate is in contact with an electrode material; and removing at leasta portion of the template to form channels in the electrode material,such as in an EC gas producer. FIG. 13A illustrates a template 1300 formaking channeled electrodes, according to an embodiment of thedisclosure. Such templates may be removed by oxidation, melting,vaporization, reduction, or any suitable means, either after theelectrochemical reactor is made or at the start of the utilization ofthe reactor.

In an embodiment, the channeled electrode material comprises NiO, YSZ,GDC, LSM, LSCF, or combinations thereof. The channeled electrodematerial may comprise any material previously described herein for acathode or anode. In an embodiment, providing a template comprisesprinting the template or precursors that assemble to form the template.Providing a template comprises polymerizing one or more monomers or aphoto-initiator, or both. In an embodiment, the method comprises curingmonomers and/or oligomers, through internal or external techniques. Invarious embodiments, internal techniques include polymerization by freeradical molecular initiation, and/or initiation by in situreduction/oxidation. In various embodiments, external techniques includephotolysis, exposure to ionizing radiation, (ultra)sonication andthermal decomposition to form the initiator species. In a preferredembodiment, said curing comprises UV curing. In an embodiment, themethod comprises adding a polymerizing agent, wherein the polymerizingagent comprises a photo-initiator. In an embodiment, the polymerizingagent is printed on top of the monomer or printed within each slice ofthe monomer.

In an embodiment, providing a template comprises dispersing metal oxideparticles in a monomer ink before printing the template. In anembodiment, the metal oxide comprises NiO, CuO, LSM (lanthanum strontiummanganite), LSCF (lanthanum strontium cobalt ferrite), GDC (gadoliniumdoped ceria), SDC (samaria-doped ceria), or combinations thereof. In anembodiment, said monomer comprises alcohol, aldehyde, carboxylic acid,ester, and/or ether functional groups. In an embodiment, said templatecomprises NiO, Cu(I)O, Cu(II)O, an organic compound, a photopolymer, orcombinations thereof.

In an embodiment, removing at least a portion of the template comprisesheating, combustion, solvent treatment, oxidation, reduction, orcombinations thereof. In an embodiment, the combustion leaves nodeposits and is not explosive. In an embodiment, the reduction takesplace in a metal oxide and produces porous template. In an embodiment,the method of providing a template comprises heating in situ.

In an embodiment, the template and electrode material are printed sliceby slice and a second slice is printed atop a first slice before thefirst slice is heated, wherein the heating removes at least a portion ofthe template. In an embodiment, the heating comprises EMR. In anembodiment, EMR comprises one or more of UV light, near ultravioletlight, near infrared light, infrared light, visible light, laser,electron beam.

In an embodiment, the channels and the electrode material form anelectrode layer. In an embodiment, the channels have regulartrajectories within the electrode layer. For example, the channels areparallel to one another. The channels may run from one end, edge, orcorner of the electrode layer to the opposite end, edge or corner. Thechannels may run from one end, edge or corner of the electrode, turn 90degrees to another end, edge or corner. The channels have randomtrajectories within the electrode layer. For example, the channels mayhave tortuous trajectories with no regularities. The channels may havemore than one entry point and more than one exit point. The more thanone entry point and the more than one exit point are distributed acrossthe electrode layer. The entry points and the exits points of thechannels in the electrode layer may be on any side of the electrodelayer, including the top surface or side and the bottom surface or side.

In some embodiments, the volume fraction of the template in theelectrode layer is in the range of 5%-95%, or 10%-90%, or 20%-80%, or30%-70%, or 40%-60%. The volume fraction of the channels in theelectrode layer is in the range of 10%-90%, or 20%-80%, or 30%-70%, or40%-60%. The total effective porosity of the electrode layer withchannels is preferably in the range of 20%-80%, or 30%-70%, or 40%-60%.Such total effective porosity of the electrode layer with channels is noless than the porosity of the electrode material. The tortuosity of theelectrode layer with channels is no greater than the native tortuosityof the electrode material.

In preferred embodiments, the gas channels span the height of theelectrode layer. The gas channels may occupy a height that is less thanthat of the electrode layer. As an example, the electrode layer is about50 microns thick. In an embodiment, the gas channel width is no lessthan 10 microns. In an embodiment, the gas channel width is no less than100 microns.

Also discussed herein is a method comprising (a) printing a firsttemplate and a first electrode material to form a first electrode layer,wherein the first template is in contact with the first electrodematerial; (b) printing an electrolyte layer; (c) printing a secondtemplate and a second electrode material to form a second electrodelayer, wherein the second template is in contact with the secondelectrode material; and (d) printing an interconnect. In a preferredembodiment, the steps are performed in any sequence. In a preferredembodiment, the method comprises repeating steps (a)-(d) in any sequenceto form a stack or a repeat unit of a stack.

In an embodiment, the method comprises (e) removing at least a portionof the first template and of the second template to form channels in thefirst and second electrode layers. In an embodiment, the removingcomprises heating, combustion, solvent treatment, oxidation, reduction,or combinations thereof. In an embodiment, the removing takes place insitu. Removing may take place after a stack or a repeat unit of a stackis printed. Removing may take place when a stack is initiated tooperate. In an embodiment, the printing takes place slice by slice and asecond slice is printed atop a first slice before the first slice isheated, wherein the heating removes at least a portion of the template.The printing step comprises material jetting, binder jetting, inkjetprinting, aerosol jetting, or aerosol jet printing, or combinationsthereof.

Further discussed herein is a method comprising (a) printing a firstelectrode layer; (b) printing an electrolyte layer; (c) printing asecond electrode layer; and (d) printing an interconnect. In anembodiment, the printing comprises material jetting, binder jetting,inkjet printing, aerosol jetting, or aerosol jet printing. In apreferred embodiment, the steps are performed in any sequence. In apreferred embodiment, the method comprises repeating steps (a)-(d) inany sequence to form a stack or a repeat unit of a stack. Also disclosedherein is a method comprising aerosol jetting or aerosol jet printing anelectrode layer, or an electrolyte layer, or an interconnect, orcombinations thereof.

FIG. 13B is a cross-sectional view of a half cell between a firstinterconnect and an electrolyte, according to an embodiment of thedisclosure. The stack in FIG. 13B comprises a bottom/first interconnect1301, an optional layer that contains the bottom interconnect materialand first electrode material 1302, first electrode segments 1303, firstfiller materials that form a first template 1304 and electrolyte 1305.

FIG. 13C is a cross-sectional view of a half cell between a secondinterconnect and an electrolyte, according to an embodiment of thedisclosure. The half cell comprises an electrolyte 1305, secondelectrode segments 1306, filler materials that forms a second template1307 and a top/second interconnect 1308. The views shown in FIG. 13B andFIG. 13C are perpendicular to one another.

FIG. 13D is a cross-sectional view of a half cell between a firstinterconnect and an electrolyte, according to an embodiment of thedisclosure. The half cell comprises a bottom interconnect 1301, anoptional layer that contains the bottom interconnect material and firstelectrode material 1302, first electrode segments 1303, first fillermaterials that forms a first template 1304, electrolyte 1305 andoptional shields 1409 for the first filler materials when the firstelectrode is heated and/or sintered.

FIG. 13E is a cross-sectional view of a half cell between a secondinterconnect and an electrolyte, according to an embodiment of thedisclosure. The half cell comprises an electrolyte 1305, secondelectrode segments 1306, filler materials that forms a second template1307, top interconnect 1308 and optional shields for the second fillermaterials when the top interconnect is heated and/or sintered. The viewsshown in FIG. 13D and FIG. 13E are perpendicular to one another.

In some embodiments, there is a layer between 1307 and 1308 (not shown)that contains the top interconnect material and second electrodematerial. In some embodiments, 1305 represents an electrolyte with abarrier for the first electrode or for second electrode. 1309 representsoptional shields for the first fillers when the first electrode isheated/sintered. 1310 represents optional shields for the second fillerswhen the top interconnect is heated/sintered. In some instances,electrolyte 1305 or electrolyte-barrier layer is in contact with thefirst electrode and the second electrode continuously along its opposingmajor faces. The shapes of the electrode segments and the fillers inthese cross-sectional views are only representative and not exact. Theymay take on any regular or irregular shapes. The fillers and/ortemplates are removed when the electrochemical reactor is made (e.g., afuel cell stack or a gas producer), for example, via heating in afurnace. Or alternatively, they are removed when the electrochemicalreactor is initiated into operation via hot gas/fluid passing through,using the effects of oxidation, melting, vaporization, gasification,reduction, or combinations thereof. These removed fillers and/ortemplates become channels in the electrodes. In various embodiments,multiple tiers of channels are present in an electrode. For anillustrative example, an electrode is 25 microns thick with amultiplicity of channels having a height of 20 microns. For anotherillustrative example, an electrode is 50 microns thick with amultiplicity of channels in 2 tiers, each tier of channels having aheight of 20 microns. In various embodiments, the fillers comprisecarbon, graphite, graphene, cellulose, metal oxides, polymethylmethacrylate, nano diamonds, or combinations thereof.

In an embodiment, a unit in an electrochemical reactor comprising aninterconnect, a first electrode, an electrolyte, and a second electrodeis made via this method: providing the interconnect, depositing a firstelectrode material in segments on the interconnect, sintering the firstelectrode material, depositing a first filler material between the firstelectrode material segments, depositing additional first electrodematerial to cover the filler material, sintering the additional firstelectrode material and forming the first electrode, depositing anelectrolyte material on the first electrode, sintering the electrolytematerial to form the electrolyte, depositing a second electrode materialon the electrolyte such that a multiplicity of valleys are formed in thesecond electrode material, sintering the second electrode material toform the second electrode, depositing a second filler material in thevalleys of the second electrode, depositing a second interconnectmaterial to cover the second electrode and the second filler material,and sintering the second interconnect material. In various embodiments,deposition is performed using inkjet printing or ultrasonic inkjetprinting. In various embodiments, sintering is performed usingelectromagnetic radiation (EMR). In some cases, the first and secondfiller materials absorb little to no EMR; the absorption is so minimalthat the filler materials have no measurable change. In some cases,shields are deposited to cover the first filler material or the secondfiller material or both so that the heating and/or sintering process forthe layer on top does not cause measurable change in the first fillermaterial or the second filler material or both. In some cases, theshields comprise YSZ, SDC, SSZ, CGO, NiO-YSZ, Cu, CuO, Cu₂O, LSM, LSCF,lanthanum chromite, stainless steel, LSGM, or combinations thereof.

Dual Porosity Electrodes

FIGS. 14A-D illustrates various embodiments of electrodes having dualporosities with one, two or three layers shown in detail that may beused in electrochemical reactors such as EC gas producers. FIG. 14Aschematically illustrates segments of fluid dispersing components in afirst layer, according to an embodiment of the disclosure. First layer1400 comprises fluid dispersing component segments 1402. Segments 1402may have different compositions, shapes, densities, porosities, poresizes, pore shapes, permeabilities, or combinations thereof. Volumefraction of channels (VFc) relative to layer 1400 containing thechannels is also shown. Herein discussed is an electrode in an ECreactor comprising a material and channels, wherein the material andchannels form a first layer in the electrode having a first layerporosity. The material has a material porosity. The channels have avolume fraction VFc, which is the ratio between the volume of thechannels and the volume of the first layer. The first layer porosityrefers to the average porosity of the first layer as a whole. The firstlayer porosity is at least 5% greater than the material porosity. TheVFc is in the range of 0-99%, or 1-30%, or 10-90%, or 5-50%, or 3-30%,or 1-50%. The VFc is no less than 5%, or 10%, or 20%, or 30%, or 40%, or50%.

FIG. 14B schematically illustrates fluid dispersing components in afirst layer along with a second layer in an electrode, according to anembodiment of the disclosure. Electrode embodiment in FIG. 14B shows afirst layer 1404 of fluid dispersing component segments 1405 and asecond layer 1406. The segments, as shown in FIG. 14B, may havedifferent compositions, shapes, densities, porosities, pore sizes, poreshapes, permeabilities, or combinations thereof. The electrode comprisesa second layer wherein the second layer has a second layer porosity. Thesecond layer porosity refers to the average porosity of the second layeras a whole. In an embodiment, said second layer porosity is no greaterthan the first layer porosity or the second layer porosity is no lessthan the first layer porosity. The second layer 1406 may comprise thesame material as in the first layer. The second layer 1406 may alsocomprise variabilities in compositions, shapes, densities, porosities,pore sizes, pore shapes, permeabilities, or combinations thereof in thelateral direction or perpendicular to the lateral direction.

FIG. 14D schematically illustrates fluid dispersing components in afirst layer 1408 along with a second layer 1412, according to anembodiment of the disclosure. The electrode embodiment in FIG. 14D issimilar to the embodiment in FIG. 14B. The electrode in FIG. 14Dcomprises a first layer 1408 further comprising fluid dispersingcomponent segments 1410, wherein segments 1410 may have differentcompositions, shapes, densities, porosities, pore sizes, pore shapes,permeabilities, or combinations thereof. The second layer 1412 maycomprise the same material as in the first layer. The second layer 1412may also comprise variabilities in compositions, shapes, densities,porosities, pore sizes, pore shapes, permeabilities, or combinationsthereof in the lateral direction or perpendicular to the lateraldirection.

FIG. 14C schematically illustrates fluid dispersing components in afirst layer along with a second and third layer, according to anembodiment of the disclosure. Electrode embodiment in FIG. 14C comprisesa first layer 1414, second layer 1416 and a third layer 1418. In anembodiment, the second layer and the third layer are on two sides of thefirst layer. In an embodiment, the second layer and the third layer arein continuous contact with two sides of the first layer. First layer1414 may comprises segments 1420 that have different compositions,shapes, densities, porosities, pore sizes, pore shapes, permeabilities,or combinations thereof. The second layer or the third layer maycomprise the same material as in the first layer. The second layer orthe third layer may also comprise variabilities in compositions, shapes,densities, porosities, pore sizes, pore shapes, permeabilities, orcombinations thereof in the lateral direction or perpendicular to thelateral direction.

In an embodiment, the material porosity of the first, second or thirdlayer is in the range of 20-60%, in the range of 30-50%, in the range of30-40% or in the range of 25-35%. In an embodiment, the materialporosity is no less than 25%, or 35%, or 45%.

In an embodiment, the electrode has a thickness of no greater than 10cm, or 5 cm, or 1 cm. In an embodiment, the electrode has a thickness ofno greater than 8 mm, or 5 mm, or 1 mm. In an embodiment, the electrodehas a thickness of no greater than 100 microns, or 80 microns, or 60microns.

In an embodiment, contribution to the permeability of the first layerfrom the channels is greater than contribution to the permeability ofthe first layer from the material. In an embodiment, no less than 50%,or 70%, or 90% of the permeability of the first layer is due to thepermeability of the channels. In an embodiment, permeability of thematerial in the first layer is no greater than 50%, or no greater than10%, or no greater than 1%, or no greater than 0.001% of thepermeability of the channels in the first layer.

Herein disclosed is a method of making an electrically conductivecomponent (ECC) of an electrochemical reactor (e.g., a fuel cell)comprising: (a) depositing on a substrate a first composition comprisinga first pore former with a first pore former volume fraction VFp1; (b)depositing on the substrate a second composition comprising a secondpore former with a second pore former volume fraction VFp2, wherein saidfirst composition and second composition form a first layer in the ECC;and (c) heating the first layer such that the first pore former and thesecond pore former become empty spaces. In an embodiment, said VFp1 isin the range of 0-100%, or 10-90%, or 30-70%, or 50-100%, or 90-100%. Inan embodiment, the VFp2 is in the range of 0-100%, or 0-70%, or 25-75%,or 30-60%. In an embodiment, the heating comprises reduction reactionsor oxidation reactions, or both reduction and oxidation reactions.

FIG. 15 is an illustrative example of an electrode having dualporosities, according to an embodiment of the disclosure. FIG. 15 showsEC component 1500 comprising a channeled electrode having dualporosities. Device 1500 comprises an anode gas inlet 1501, an anode gasoutlet 1502, a cathode gas inlet 1503, and a cathode gas outlet 1504.Exploded view 1505 is a view of a portion of a cathode layer. View 1506is a closer view of the cathode wherein view 1506 represents a slicethrough the cathode layer that is composed of cathode 1507. Cathode 1507is a porous cathode that is formed using micro pore formers. Channels1508 represents channels formed from macro pore formers.

In an embodiment, (a) and (b) are accomplished via printing, or viaextrusion, or via additive manufacturing (AM), or via tape casting, orvia spraying, or via deposition, or via sputtering, or via screenprinting. In an embodiment, said additive manufacturing comprisesextrusion, photopolymerization, powder bed fusion, material jetting,binder jetting, directed energy deposition, lamination.

In an embodiment, the first pore former and the second pore former arethe same. In an embodiment, the first pore former and the second poreformer are different. In an embodiment, said first pore former or secondpore former has an average diameter in the range of 10 nm to 1 mm or 100nm to 100 microns or 500 nanometers to 50 microns. In an embodiment,said first pore former or second pore former has a size distribution. Inan embodiment, said first pore former or second pore former comprisescarbon, graphite, polymethyl methacrylate (PMMA), cellulose, metaloxides, or combinations thereof.

In an embodiment, the method comprises repeating (a) and (b) to form asecond layer in the ECC; and heating the second layer. In an embodiment,heating the second layer takes places at the same time as heating thefirst layer. In an embodiment, heating the second layer takes places ata different time as heating the first layer. In an embodiment, heatingthe second layer and heating the first layer have at least a portion ofoverlapping time period. In an embodiment, the method comprisesrepeating (a) and (b) to form a third layer in the ECC; and heating thethird layer. In an embodiment, the second layer and the third layer areon two sides of the first layer. In an embodiment, heating the first,second, and third layers is simultaneous. Alternatively, the first,second, and third layers are heated at different times. In anembodiment, heating of the first, second, and third layers hasoverlapping time periods. In an embodiment, the first, second, or thirdlayer is heated more than once.

In an embodiment, at least a portion of the empty spaces caused by thesecond pore former or the first pore former or both become channels inthe first layer. In an embodiment, the channels have a volume fractionVFc, which is the ratio between the volume of the channels and thevolume of the first layer. In an embodiment, said VFc is in the range of0-99% or 1-30% or 10-90% or 5-50% or 3-30% or 1-50%. In an embodiment,said VFc is no less than 5% or 10% or 20% or 30% or 40% or 50%.

In an embodiment, VFp1 is different from VFp2. In an embodiment, saidfirst layer has dual porosities, a material porosity and a layerporosity. In an embodiment, the material porosity is in the range of20-60%, or 30-50%, or 30-40%, or 25-35%. In an embodiment, the materialporosity is no less than 25% or 35% or 45%.

In an embodiment, the ECC has a thickness of no greater than 10 cm or 5cm or 1 cm. In an embodiment, the ECC a thickness of no greater than 8mm or 5 mm or 1 mm. In an embodiment, the ECC has a thickness of nogreater than 100 microns or 80 microns or 60 microns.

In an embodiment, the first layer comprises channels and material after(c), wherein contribution to the permeability of the first layer fromthe channels is greater than contribution to the permeability of thefirst layer from the material. In an embodiment, no less than 50% or 70%or 90% of the permeability of the first layer is due to the permeabilityof the channels. In an embodiment, permeability of the material in thefirst layer is no greater than 50% or no greater than 10% or no greaterthan 1% or no greater than 0.001% of the permeability of the channels inthe first layer.

Herein discussed is a method comprising: (a) providing a first materialto an additive manufacturing machine (AMM); (b) providing a secondmaterial to the AMM; (c) mixing the first material and the secondmaterial into a mixture; and (d) forming said mixture into a part. In anembodiment, said first material or second material is a gas, or liquid,or solid, or gel.

In an embodiment, said additive manufacturing comprises extrusion,photopolymerization, powder bed fusion, material jetting, binderjetting, directed energy deposition, lamination. In an embodiment, saidAM comprises direct metal laser sintering (DMLS), selective lasersintering (SLS), selective laser melting (SLM), directed energydeposition (DED), laser metal deposition (LMD), electron beam (EBAM), ormetal binder jetting. In an embodiment, steps (c) and (d) take placecontinuously.

In an embodiment, step (c) comprises varying the ratio of the firstmaterial and the second material in the mixture. In an embodiment, theratio of the first material and the second material in the mixture isvaried in situ. In an embodiment, the ratio of the first material andthe second material in the mixture is varied in real time. In anembodiment, the ratio of the first material and the second material inthe mixture is varied continuously. In an embodiment, the ratio of thefirst material and the second material in the mixture is variedaccording to a composition profile. In an embodiment, the ratio of thefirst material and the second material in the mixture is variedaccording to a manual algorithm, a computational algorithm, or acombination thereof. In an embodiment, the ratio of the first materialand the second material in the mixture is varied by controlling materialflow rates or pumping rates.

In an embodiment, step (d) comprises placing said mixture in a patternon a substrate. In an embodiment, step (d) comprises placing saidmixture according to pre-defined specifications.

In an embodiment, the formed part has varying properties. In anembodiment, the properties comprise strength, weight, density,electrical performance, electrochemical performance, or combinationsthereof. In various embodiments, the formed part possesses superiorproperties, such as strength, density, weight, electrical performance,or electrochemical performance, or combinations thereof, when comparedwith a similar part formed by a different process.

In an embodiment, step (d) comprises depositing said mixture on asubstrate. In an embodiment, mixing takes place prior to deposition,during deposition, or after deposition. In an embodiment, mixing takesplace in the AMM or in the air or on the substrate. In an embodiment,mixing takes place via advection, dispersion, diffusion, melting,fusion, pumping, stirring, heating, or combinations thereof.

Herein disclosed is an additive manufacturing machine (AMM) comprising:(a) a first material source; (b) a second material source; and (c) amixer configured to mix the first material and the second material intoa mixture; wherein said AMM is configured to form said mixture into apart. In an embodiment, said first material or second material is a gas,or liquid, or solid, or gel.

In an embodiment, said AMM is configured to perform extrusion,photopolymerization, powder bed fusion, material jetting, binderjetting, directed energy deposition, or lamination. In an embodiment,said AMM is configured to perform direct metal laser sintering (DMLS),selective laser sintering (SLS), selective laser melting (SLM), directedenergy deposition (DED), laser metal deposition (LMD), electron beam(EBAM), or metal binder jetting.

In an embodiment, said mixer is configured to mix the first material andthe second material continuously while the AMM forms said mixture into apart. In an embodiment, said mixer is configured to vary the ratio ofthe first material and the second material in the mixture. In anembodiment, said mixer is configured to vary the ratio of the firstmaterial and the second material in the mixture in situ. The mixer maybe configured to vary the ratio of the first material and the secondmaterial in the mixture in real time. In an embodiment, the mixer can beconfigured to vary the ratio of the first material and the secondmaterial in the mixture continuously. In an embodiment, the mixer isconfigured to vary the ratio of the first material and the secondmaterial in the mixture according to a composition profile. In anembodiment, the mixer is configured to vary the ratio of the firstmaterial and the second material in the mixture according to a manualalgorithm, a computational algorithm, or a combination thereof. In anembodiment, said mixer is configured to vary the ratio of the firstmaterial and the second material in the mixture by controlling materialflow rates or pumping rates.

In an embodiment, said AMM is configured to place said mixture in apattern on a substrate. In an embodiment, said AMM is configured toplace said mixture according to pre-defined specifications.

In an embodiment, the formed part has varying properties. In anembodiment, the properties comprise strength, weight, density,electrical performance, electrochemical performance, or combinationsthereof. In various embodiments, the formed part possesses superiorproperties, such as strength, density, weight, electrical performance,or electrochemical performance, or combinations thereof, when comparedwith a similar part formed using a different apparatus.

In an embodiment, the AMM is configured to deposit said mixture on asubstrate. In an embodiment, mixing takes place prior to deposition,during deposition, or after deposition. In an embodiment, mixing takesplace in the AMM or in the air or on the substrate. In an embodiment,mixing takes place via advection, dispersion, diffusion, melting,fusion, pumping, stirring, heating, or combinations thereof.

Integrated Deposition and Heating

Disclosed herein is a method comprising depositing a composition on asubstrate slice by slice (this may also be described as line-by-linedeposition) to form an object; heating in situ the object usingelectromagnetic radiation (EMR); wherein said composition comprises afirst material and a second material, wherein the second material has ahigher absorbance of EMR than the first material. In variousembodiments, heating may cause an effect comprising drying, curing,sintering, annealing, sealing, alloying, evaporating, restructuring,foaming or combinations thereof. In some embodiments, the EMR has a peakwavelength ranging from 10 to 1500 nm and a minimum energy density of0.1 Joule/cm² wherein the peak wavelength is on the basis of irradiancewith respect to wavelength. In some embodiments, the EMR comprises oneor more of UV light, near ultraviolet light, near infrared light,infrared light, visible light, laser or electron beam.

FIG. 16 illustrates a system for integrated deposition and heating usingelectromagnetic radiation (EMR), according to an embodiment of thedisclosure. The system 1600 may be used to assemble an electrochemicalreactor such as a fuel cell or EC gas producer. FIG. 16 furtherillustrates system 1600 an object 1603 on a receiver 1604 formed bydeposition nozzles 1601 and EMR 1602 for heating in situ, according toan embodiment of this disclosure. Receiver 1604 may be a platform thatmoves and may further receive deposition, heat, irradiation, orcombinations thereof. Receiver 1604 may also be referred to as a chamberwherein the chamber may be completely enclosed, partially enclosed orcompletely open to the atmosphere.

In some embodiments, the first material comprises yttria-stabilizedzirconia (YSZ), 8YSZ (8 mol % YSZ powder), yttrium, zirconium,gadolinia-doped ceria (GDC or CGO), samaria-doped ceria (SDC),scandia-stabilized zirconia (SSZ), lanthanum strontium manganite (LSM),lanthanum strontium cobalt ferrite (LSCF), lanthanum strontium cobaltite(LSC), lanthanum strontium gallium magnesium oxide (LSGM), nickel, NiO,NiO-YSZ, Cu-CGO, Cu₂O, CuO, cerium, copper, silver, crofer, steel,lanthanum chromite, doped lanthanum chromite, ferritic steel, stainlesssteel or combinations thereof. In other embodiments, the first materialcomprises YSZ, SSZ, CGO, SDC, NiO-YSZ, LSM-YSZ, CGO-LSCF, dopedlanthanum chromite, stainless steel or combinations thereof. In someembodiments, the second material comprises carbon, nickel oxide, nickel,silver, copper, CGO, SDC, NiO-YSZ, NiO-SSZ, LSCF, LSM, doped lanthanumchromite ferritic steels or combinations thereof. The first material maycomprise any electrode material previously disclosed herein.

In some embodiments, object 1603 comprises a catalyst, a catalystsupport, a catalyst composite, an anode, a cathode, an electrolyte, anelectrode, an interconnect, a seal, a fuel cell, an electrochemical gasproducer, an electrolyser, an electrochemical compressor, a reactor, aheat exchanger, a vessel or combinations thereof.

In some embodiments, the second material may be deposited in the sameslice as the first material. In other embodiments, the second materialmay be deposited in a slice adjacent another slice that contains thefirst material. In some embodiments, said heating may remove at least aportion of the second material. In preferred embodiments, said heatingleaves minimal residue of the second material such that there is nosignificant residue that would interfere with the subsequent steps inthe process or the operation of the device being constructed. Morepreferably, this leaves no measurable reside of the portion of thesecond material.

In some embodiments, the second material may add thermal energy to thefirst material during heating. In other embodiments, the second materialhas a radiation absorbance that is at least 5 times that of the firstmaterial; the second material has a radiation absorbance that is atleast 10 times that of the first material; the second material has aradiation absorbance that is at least 50 times that of the firstmaterial or the second material has a radiation absorbance that is atleast 100 times that of the first material.

In some embodiments, the second material may have a peak absorbancewavelength no less than 200 nm, or 250 nm, or 300 nm, or 400 nm, or 500nm. In other embodiments, the first material has a peak absorbancewavelength no greater than 700 nm, or 600 nm, or 500 nm, or 400 nm, or300 nm. In other embodiments, the EMR has a peak wavelength no less than200 nm, or 250 nm, or 300 nm, or 400 nm, or 500 nm.

In some embodiments, the second material may comprise carbon, nickeloxide, nickel, silver, copper, CGO, NiO-YSZ, LSCF, LSM, ferritic steels,other metal oxides or combinations thereof. In some cases, the ferriticsteel is Crofer 22 APU. In some embodiments, the first materialcomprises YSZ, CGO, NiO-YSZ, LSM-YSZ, other metal oxides or combinationsthereof. In an embodiment, the second material comprises LSCF, LSM,carbon, nickel oxide, nickel, silver, copper, or steel. In someembodiments, carbon comprises graphite, graphene, carbon nanoparticles,nano diamonds or combinations thereof. The second material may compriseany electrode material previously disclosed herein.

In some embodiments, the deposition method comprises material jetting,binder jetting, inkjet printing, aerosol jetting, aerosol jet printing,vat photopolymerization, powder bed fusion, material extrusion, directedenergy deposition, sheet lamination, ultrasonic inkjet printing orcombinations thereof.

In some embodiments, the deposition method further comprises one or moreof the steps of controlling distance from the EMR to the receiver, EMRenergy density, EMR spectrum, EMR voltage, EMR exposure duration, EMRexposure area, EMR exposure volume, EMR burst frequency, EMR exposurerepetition number. In an embodiment, the object does not change locationbetween the deposition and heating steps. In an embodiment, the EMR hasa power output of no less than 1 W, or 10 W, or 100 W, or 1000 W.

Also disclosed herein is a system comprising at least one depositionnozzle, an electromagnetic radiation (EMR) source and a depositionreceiver, wherein the deposition receiver is configured to receive EMRexposure and deposition at the same location. In some cases, thereceiver is configured such that it receives deposition for a first timeperiod, moves to a different location in the system to receive EMRexposure for a second time period.

The following detailed description describes the production of solidoxide fuel cells (SOFCs) for illustrative purposes. As one in the artrecognizes, the methodology and the manufacturing processes areapplicable to all fuel cell types. As such, the production of all fuelcell types is within the scope of this disclosure.

Additive Manufacturing

Additive manufacturing (AM) refers to a group of techniques that joinmaterials to make objects, usually slice by slice or layer upon layer.AM is contrasted to subtractive manufacturing methodologies, whichinvolve removing sections of a material by machining, cutting, grindingor etching away. AM may also be referred to as additive fabrication,additive processes, additive techniques, additive layer manufacturing,layer manufacturing or freeform fabrication. Some examples of AM areextrusion, photopolymerization, powder bed fusion, material jetting,binder jetting, directed energy deposition, lamination, direct metallaser sintering (DMLS), selective laser sintering (SLS), selective lasermelting (SLM), directed energy deposition (DED), laser metal deposition(LMD), electron beam (EBAM) and metal binder jetting. A 3D printer is atype of AM machine (AMM). An inkjet printer or ultrasonic inkjet printerare additional examples of AMMs.

In a first aspect, the invention is a method of making anelectrochemical reactor such as a EC gas producer or a fuel cellcomprising: (a) producing an anode using an AMM; (b) creating anelectrolyte using the AMM; and (c) making a cathode using the AMM. Inpreferred embodiments, the anode, the electrolyte and the cathode areassembled into a fuel cell utilizing an AMM in addition to other stepsthat are not completed using an AMM. In a preferred embodiment, the fuelcell is formed using only the AMM. In other embodiments, steps (a), (b),and (c) exclude tape casting and screen printing. In an embodiment, themethod of assembling a fuel cell with an AMM excludes compression inassembling. In other embodiments, the layers are deposited one on top ofanother in a step-wise manner such that assembling is accomplished atthe same time as deposition. The methods described herein are useful inmaking planar fuel cells. The methods described herein are also usefulin making fuel cell, wherein electrical current flow is perpendicular tothe electrolyte in the lateral direction when the fuel cell is in use.

In an embodiment, the interconnect, the anode, the electrolyte, and thecathode are formed layer on layer, for example, printed layer on layer.It is important to note that, within the scope of the invention, theorder of forming these layers can be varied. In other words, either theanode or the cathode can be formed before the other. Naturally, theelectrolyte is formed so that it is between the anode and the cathode.Barrier layer(s), catalyst layer(s) and interconnect(s) are formed so asto lie in the appropriate position within the fuel cell to perform theirfunctions.

In some embodiments, each of the interconnect, the anode, theelectrolyte and the cathode have six faces. In preferred embodiments,the anode is printed on the interconnect and is in contact with theinterconnect; the electrolyte is printed on the anode and is in contactwith the anode; the cathode is printed on the electrolyte and is incontact with the electrolyte. Each print may be sintered, for example,using EMR. As such, the assembly process and the forming process aresimultaneous, which is not possible with conventional methods. Moreover,with the preferred embodiment, the needed electrical contact and gastightness are also achieved at the same time. In contrast, conventionalfuel cell assembly processes accomplish this via pressing or compressionof the fuel cell components or layers. The pressing and compressionprocesses can cause cracks in the fuel cell layers that are undesirable.

In some embodiments, the AM method comprises making at least one barrierlayer using the AMM. In preferred embodiments, the at least one barrierlayer may be located between the electrolyte and the cathode or betweenthe electrolyte and the anode or both. In other embodiments, the atleast one barrier layer may be assembled with the anode, the electrolyteand the cathode using the AMM. In some embodiments, no barrier layer isneeded or utilized in the fuel cell.

In some embodiments, the AM method comprises making an interconnectusing the AMM. In other embodiments, the interconnect may be assembledwith the anode, the electrolyte and the cathode using the AMM. In someembodiments, the AMM forms a catalyst and incorporates said catalystinto the fuel cell.

In some embodiments, the anode, the electrolyte, the cathode and theinterconnect are made at a temperature above 100° C. In some embodiment,the AM method comprises heating the fuel cell, wherein said fuel cellcomprises the anode, the electrolyte, the cathode, the interconnect andoptionally at least one barrier layer. In some embodiments, the fuelcell comprises a catalyst. In some embodiments, the method comprisesheating the fuel cell to a temperature above 500° C. In someembodiments, the fuel cell is heated using one or both of EMR or ovencuring.

In a preferred embodiment, the AMM utilizes a multi-nozzle additivemanufacturing method. In a preferred embodiment, the multi-nozzleadditive manufacturing method comprises nanoparticle jetting. In someembodiments, a first nozzle delivers a first material, a second nozzledelivers a second material, a third nozzle delivers a third material. Insome embodiments, particles of a fourth material are placed in contactwith a partially constructed fuel cell and bonded to the partiallyconstructed fuel cell using a laser, photoelectric effect, light, heat,polymerization or binding. In an embodiment, the anode, the cathode orthe electrolyte comprises a first, second, third or fourth material. Inpreferred embodiments, the AMM performs multiple AM techniques. Invarious embodiments, the AM techniques comprise one or more ofextrusion, photopolymerization, powder bed fusion, material jetting,binder jetting, directed energy deposition or lamination. In variousembodiments, AM is a deposition technique comprising material jetting,binder jetting, inkjet printing, aerosol jetting, or aerosol jetprinting, vat photopolymerization, powder bed fusion, materialextrusion, directed energy deposition, sheet lamination, ultrasonicinkjet printing or combinations thereof.

Further described herein is an AM method of making a fuel cell stackcomprising: (a) producing an anode using an additive manufacturingmachine (AMM); (b) creating an electrolyte using the AMM; (c) making acathode using the AMM; (d) making an interconnect using the AMM; whereinthe anode, the electrolyte, the cathode, and the interconnect form afirst fuel cell; (e) repeating steps (a)-(d) to make a second fuel cell;and (f) assembling the first fuel cell and the second fuel cell into afuel cell stack.

In some embodiments, the first fuel cell and the second fuel cell areformed from the anode, the electrolyte, the cathode and the interconnectutilizing the AMM. In an embodiment, the fuel cell stack is formed usingonly the AMM. In other embodiments, steps (a)-(f) exclude one or both oftape casting and screen printing.

In some embodiments, the AM method comprises making at least one barrierlayer using the AMM. In some embodiments, the at least one barrier layeris located between the electrolyte and the cathode or between theelectrolyte and the anode or both for the first fuel cell and the secondfuel cell.

In some embodiments, steps (a)-(d) are performed at a temperature above100° C. In other embodiments, steps (a)-(d) are performed at atemperature in the range of 100° C. to 500° C. In some embodiments, theAMM makes a catalyst and incorporates said catalyst into the fuel cellstack.

In some embodiments, the AM method comprises heating the fuel cellstack. In an embodiment, the AM method comprises heating the fuel cellstack to a temperature above 500° C. In some embodiments, the fuel cellstack is heated using EMR and/or oven curing. In some embodiments, thelaser has a laser beam, wherein the laser beam is expanded to create aheating zone with uniform power density. In some embodiments, the laserbeam is expanded by utilizing one or more mirrors. In some embodiments,each layer of the fuel cell may be cured separately by EMR. In someembodiments, a combination of one or more fuel cell layers may be curedtogether by EMR. In some embodiments, the first fuel cell is EMR cured,assembled with the second fuel cell, and then the second fuel cell isEMR cured. In other embodiments, the first fuel cell is assembled withthe second fuel cell, and then the first fuel cell and the second fuelcell are cured separately by EMR. In some embodiments, the first fuelcell and the second fuel cell may be cured separately by EMR, and thenthe first fuel cell is assembled with the second fuel cell to form afuel cell stack. In some embodiments, the first fuel cell is assembledwith the second fuel cell to form a fuel cell stack, and then the fuelcell stack may be cured by EMR.

Also discussed herein is an AM method of making a multiplicity of fuelcells comprising (a) producing a multiplicity of anodes simultaneouslyusing an additive manufacturing machine (AMM); (b) creating amultiplicity of electrolytes using the AMM simultaneously; and (c)making a multiplicity of cathodes using the AMM simultaneously. Inpreferred embodiments, the anodes, the electrolytes and cathodes areassembled into fuel cells utilizing the AMM simultaneously. In otherpreferred embodiments, the fuel cells are formed using only the AMM.

In some embodiments, the method comprises making at least one barrierlayer using the AMM for each of the multiplicity of fuel cellssimultaneously. The at least one barrier layer may be located betweenthe electrolyte and the cathode or located between the electrolyte andthe anode, or both. In preferred embodiments, the at least one barrierlayer may be assembled with the anode, the electrolyte and the cathodeusing the AMM for each fuel cell.

In some embodiments, the method comprises making an interconnect usingthe AMM for each of the multiplicity of fuel cells simultaneously. Theinterconnect may be assembled with the anode, the electrolyte and thecathode using the AMM for each fuel cell. In other embodiments, the AMMforms a catalyst for each of the multiplicity of fuel cellssimultaneously and incorporates said catalyst into each of the fuelcells. In other embodiments, heating each layer or heating a combinationof layers of the multiplicity of fuel cells takes place simultaneously.The multiplicity of fuel cells may include two or more fuel cells.

In preferred embodiments, the AMM uses two or more different nozzles tojet or print different materials at the same time. For a first example,in an AMM, a first nozzle deposits an anode layer for fuel cell 1, asecond nozzle deposits a cathode layer for fuel cell 2 and a thirdnozzle deposits an electrolyte for fuel cell 3, at the same time. For asecond example, in an AMM, a first nozzle deposits an anode for fuelcell 1, a second nozzle deposits a cathode for fuel cell 2, a thirdnozzle deposits an electrolyte for fuel cell 3 and a fourth nozzledeposits an interconnect for fuel cell 4, at the same time.

Disclosed herein is an additive manufacturing machine (AMM) comprising achamber wherein manufacturing of fuel cells takes place. Said chamber isable to withstand temperatures of at least 100° C. In an embodiment,said chamber enables production of the fuel cells. The chamber enablesheating of the fuel cells in situ as the components of the fuel cell arebeing deposited.

In some embodiments, the chamber may be heated by laser, electromagneticwaves/electromagnetic radiation (EMR), hot fluid or a heating elementassociated with the chamber, or combinations thereof. The heatingelement may comprise a heated surface, heating coil or a heating rod. Inother embodiments, said chamber may be configured to apply pressure tothe fuel cells inside. The pressure may be applied via a moving elementassociated with the chamber. The moving element may be a moving stamp orplunger. In some embodiments, said chamber may be configured towithstand pressure. the chamber may be configured to be pressurized ordepressurized by a fluid. The fluid in the chamber may be changed orreplaced when needed.

In some cases, the chamber may be enclosed. In some cases, the chambermay be sealed. In some cases, the chamber may be open to ambientatmosphere or to a controlled atmosphere. In some cases, the chamber maybe a platform without top and side walls.

Referring to FIG. 16, system 1600 comprises deposition nozzles ormaterial jetting nozzles 1601, EMR source 1602 (e.g., xenon lamp),object being formed 1603, and chamber or receiver 1604 as a part of anAMM. As illustrated in FIG. 16, the chamber or received 604 isconfigured to receive both deposition from nozzles and radiation fromEMR source 1602. In various embodiments, deposition nozzles 1601 may bemovable. In various embodiments, the chamber or receiver 1604 may bemovable. In various embodiments, EMR source 1602 is movable. In variousembodiments, the object comprises a catalyst, a catalyst support, acatalyst composite, an anode, a cathode, an electrolyte, an electrode,an interconnect, a seal, a fuel cell, an electrochemical gas producer,an electrolyser, an electrochemical compressor, a reactor, a heatexchanger, a vessel or combinations thereof.

AM techniques suitable for this disclosure comprise extrusion,photopolymerization, powder bed fusion, material jetting, binderjetting, directed energy deposition and lamination. In some embodiments,extrusion may be used for AM. Extrusion AM involves the spatiallycontrolled deposition of material (e.g., thermoplastics). Extrusion AMmay also be referred to as fused filament fabrication (FFF) or fuseddeposition modeling (FDM) in this disclosure.

In some embodiments, AM comprises photopolymerization (i.e.,stereolithography (SLA)) for the process of this disclosure. SLAinvolves spatially-defined curing of a photoactive liquid (a“photoresin”), using a scanning laser or a high-resolution projectedimage, and transforming the photoactive liquid into a crosslinked solid.Photopolymerization can produces parts with details and dimensionsranging from the micrometer- to meter-scales.

In some embodiments, AM comprises powder bed fusion (PBF). PBF AMprocesses build objects by melting powdered feedstock, such as a polymeror metal. PBF processes begin by spreading a thin layer of powder acrossa build area. Cross-sections are then melted a layer at a time, mostoften using a laser, electron beam or intense infrared lamps. In someembodiments, PBF of metals may use selective laser melting (SLM) orelectron beam melting (EBM). In other embodiments, PBF of polymers mayuse selective laser sintering (SLS). In various embodiments, SLS systemsmay print thermoplastic polymer materials, polymer composites orceramics. In various embodiments, SLM systems may be suitable for avariety of pure metals and alloys, wherein the alloys are compatiblewith rapid solidification that occurs in SLM.

In some embodiments, AM may comprise material jetting. AM by materialjetting may be accomplished by depositing small drops (or droplets) ofmaterial with spatial control. In various embodiments, material jettingis performed three dimensionally (3D), two dimensionally (2D) or both.In preferred embodiments, 3D jetting is accomplished layer by layer. Inpreferred embodiments, print preparation converts the computer-aideddesign (CAD), along with specifications of material composition, color,and other variables to the printing instructions for each layer. Binderjetting AM involves inkjet deposition of a liquid binder onto a powderbed. In some cases, binder jetting is combined with other AM processes,such as for example, spreading of powder to make the powder bed(analogous to SLS/SLM) and inkjet printing.

In some embodiments, AM comprises directed energy deposition (DED).Instead of using a powder bed as discussed above, the DED process uses adirected flow of powder or a wire feed, along with an energy intensivesource such as laser, electric arc or electron beam. In preferredembodiments, DED is a direct-write process, wherein the location ofmaterial deposition is determined by movement of the deposition headwhich allows large metal structures to be built without the constraintsof a powder bed.

In some embodiments, AM comprises lamination AM or laminated objectmanufacturing (LOM). In preferred embodiments, consecutive layers ofsheet material are consecutively bonded and cut in order to form a 3Dstructure.

Traditional methods of manufacturing a fuel cell stack can comprise over100 steps. These steps may include, but not limited to, milling,grinding, filtering, analyzing, mixing, binding, evaporating, aging,drying, extruding, spreading, tape casting, screen printing, stacking,heating, pressing, sintering and compressing. The methods disclosedherein describe manufacturing of a fuel cell or fuel cell stack usingone AMM.

The AMM of this disclosure preferably performs both extrusion and inkjetting to manufacture a fuel cell or fuel cell stack. Extrusion may beused to manufacture thicker layers of a fuel cell, such as, the anodeand/or the cathode. Ink jetting may be used to manufacture thin layersof a fuel cell. Ink jetting may be used to manufacture the electrolyte.The AMM may operate at temperature ranges sufficient to enable curing inthe AMM itself. Such temperature ranges are 100° C. or above, 100-300°C. or 100-500° C.

As a preferred example, all layers of a fuel cell are formed andassembled via printing. The material for making the anode, cathode,electrolyte and the interconnect, respectively, may be made into an inkform comprising a solvent and particles (e.g., nanoparticles). There aretwo categories of ink formulations—aqueous inks and non-aqueous inks. Insome cases, the aqueous ink comprises an aqueous solvent (e.g., water,deionized water), particles, dispersant and a surfactant. In some cases,the aqueous ink comprises an aqueous solvent, particles, dispersant,surfactant but no polymeric binder. The aqueous ink may optionallycomprise a co-solvent, such as an organic miscible solvent (methanol,ethanol, isopropyl alcohol). Such co-solvents preferably have a lowerboiling point than water. The dispersant may be an electrostaticdispersant, steric dispersant, ionic dispersant, or a non-ionicdispersant, or a combination thereof. The surfactant may preferably benon-ionic, such as an alcohol alkoxylate or an alcohol ethoxylate. Thenon-aqueous ink may comprise an organic solvent (e.g., methanol,ethanol, isopropyl alcohol, butanol) and particles.

For example, CGO powder is mixed with water to form an aqueous inkfurther comprising a dispersant and a surfactant but with no polymericbinder added. The CGO fraction based on mass (herein expressed as weight% (wt %)) is in the range of 10 wt % to 25 wt %. For example, CGO powderis mixed with ethanol to form a non-aqueous ink further comprisingpolyvinyl butaryl added with the CGO fraction in the range of 3 wt % to30 wt %. For example, LSCF is mixed with n-butanol or ethanol to form anon-aqueous ink further comprising polyvinyl butaryl with the LSCFfraction in the range of 10 wt % to 40 wt %. For example, YSZ particlesare mixed with water to form an aqueous ink further comprising adispersant and surfactant but with no polymeric binder added. The YSZfraction is in the range of 3 wt % to 40 wt %. For example, NiOparticles are mixed with water to form an aqueous ink further comprisinga dispersant and surfactant but with no polymeric binder added with theNiO fraction in the range of 5 wt % to 25 wt %.

As an example, for the cathode of a fuel cell, LSCF or LSM particles aredissolved in a solvent, wherein the solvent is water or an alcohol(e.g., butanol) or a mixture of alcohols. Organic solvents other thanalcohols may also be used in other examples. As an example, LSCF isdeposited (e.g., printed) into a layer. A xenon lamp may be used toirradiate the LSCF layer with EMR to sinter the LSCF particles. Thexenon flash lamp may be a 10 kW unit applied at a voltage of 400V and afrequency of 10 Hz for a total exposure duration of 1000 ms.

For example, for the electrolyte, YSZ particles are mixed with asolvent, wherein the solvent is water (e.g., de-ionized water) or analcohol (e.g., butanol) or a mixture of alcohols. Organic solvents otherthan alcohols may also be used in other examples. For the interconnect,metallic particles (e.g., silver nanoparticles) are dissolved in asolvent, wherein the solvent may comprise water (e.g., de-ionized water)and an organic solvent. The organic solvent may comprise mono-, di-, ortri-ethylene glycols or higher ethylene glycols, propylene glycol,1,4-butanediol or ethers of such glycols, thiodiglycol, glycerol andethers and esters thereof, polyglycerol, mono-, di-, andtri-ethanolamine, propanolamine, N,N-dimethylformamide, dimethylsulfoxide, dirnethylacetamide, N-methylpyrrolidone,1,3-dimethylimidazolidone, methanol, ethanol, isopropanol, n-propanol,diacetone alcohol, acetone, methyl ethyl ketone or propylene carbonate,or combinations thereof. For a barrier layer in a fuel cell, CGOparticles are dissolved in a solvent, wherein the solvent may be water(e.g., de-ionized water) or an alcohol. The alcohol may comprisemethanol, ethanol, butanol or a mixture of alcohols. Organic solventsother than alcohols may also be used. CGO may be used as barrier layerfor LSCF. YSZ may also be used as a barrier layer for LSM. In somecases, for the aqueous inks where water is the solvent, no polymericbinder may be added to the aqueous inks.

The manufacturing process of a conventional fuel cell sometimescomprises more than 100 steps and utilizing dozens of machines.According to an embodiment of this disclosure, a method of making a fuelcell comprises using only one AMM to manufacture a fuel cell, whereinthe fuel cell comprises an anode, electrolyte and a cathode. Inpreferred embodiments, the fuel cell comprises at least one barrierlayer, for example, between the electrolyte and the cathode, or betweenthe electrolyte and the cathode, or both. The at least one barrier layeris preferably also made by the same AMM. In preferred embodiments, theAMM may also produce an interconnect and assembles the interconnect withthe anode, cathode, at least one barrier layer and the electrolyte. Suchmanufacturing methods and systems are applicable not only to making fuelcells but also for making other types of electrochemical devices. Thefollowing discussion uses fuel cells as an example, but any reactor orcatalyst is within the scope of this disclosure.

In various embodiments, a single AMM makes a first fuel cell, whereinthe fuel cell comprises an anode, electrolyte, cathode, at least onebarrier layer and an interconnect. In various embodiments, a single AMMmakes a second fuel cell. In various embodiments, a single AMM is usedto assemble a first fuel cell with a second fuel cell to form a fuelcell stack. In various embodiments, the production of fuel cells usingan AMM is repeated as many times as desired. A fuel cell stackcomprising two or more fuel cells is thus assembled using an AMM. Insome embodiments, the various layers of the fuel cell are produced by anAMM above ambient temperature. For example, the temperatures may beabove 100° C., in the range of 100° C. to 500° C. or in the range of100° C. to 300° C. In various embodiments, a fuel cell or fuel cellstack is heated after it is assembled. In some embodiments, the fuelcell or fuel cell stack is heated at a temperature above 500° C. Inpreferred embodiments, the fuel cell or fuel cell stack is heated at atemperature in the range of 500° C. to 1500° C.

In various embodiments, an AMM comprises a chamber where themanufacturing of fuel cells takes place. This chamber may be able towithstand high temperature to enable the production of the fuel cellswherein the high temperature is at least 300° C., at least 500° C., atleast 1000° C. or at least 1500° C. In some cases, this chamber may alsoenable the heating of the fuel cells to take place in the chamber.Various heating methods may be applied, such as laser heating/curing,electromagnetic wave heating, hot fluid heating or one or more heatingelements associated with the chamber. The heating element may be aheating surface, heating coil or a heating rod and is associated withthe chamber such that the content in the chamber is heated to thedesired temperature range. In various embodiments, the chamber of theAMM may also be able to apply pressure to the fuel cell(s) inside. Forexample, a pressure may be applied via a moving element, such as amoving stamp or plunger. In various embodiments, the chamber of the AMMis able to withstand pressure. The chamber can be pressurized ordepressurized as desired by a fluid. The fluid in the chamber can alsobe changed or replaced as needed.

In preferred embodiments, a fuel cell or fuel cell stack is heated usingEMR. In other embodiments, the fuel cell or fuel cell stack may beheated using oven curing. In other embodiments, the laser beam may beexpanded (for example, by the use of one or more mirrors) to create aheating zone with uniform power density. In a preferred embodiment, eachlayer of the fuel cell may be cured by EMR separately. In preferredembodiments, a combination of fuel cell layers may be EMR curedseparately, for example, a combination of the anode, the electrolyte,and the cathode layers. In some embodiments, a first fuel cell is EMRcured, assembled with a second fuel cell, and then the second fuel cellis EMR cured. In an embodiment, a first fuel cell is assembled with asecond fuel cell, and then the first fuel cell and the second fuel cellare EMR cured separately. In an embodiment, a first fuel cell isassembled with a second fuel cell to form a fuel cell stack, and thenthe fuel cell stack is EMR cured. A fuel cell stack comprising two ormore fuel cells may be EMR cured. The sequence of laser heating/curingand assembling is applicable to all other heating methods.

In preferred embodiments, an AMM produces each layer of a multiplicityof fuel cells simultaneously. In preferred embodiments, the AMMassembles each layer of a multiplicity of fuel cells simultaneously. Inpreferred embodiments, heating each layer or heating a combination oflayers of a multiplicity of fuel cells takes place simultaneously. Allthe discussion and all the features described herein for a fuel cell ora fuel cell stack are applicable to the production, assembling andheating of the multiplicity of fuel cells. In preferred embodiments, amultiplicity of fuel cells may be 2 or more 20 or more, 50 or more,80 ormore, 100 or more, 500 or more, 800 or more, 1000 or more, 5000 or moreor 10,000 or more.

Treatment Process

Herein disclosed is a treatment process that comprises one or more ofthe following effects: heating, drying, curing, sintering, annealing,sealing, alloying, evaporating, restructuring, foaming or sintering. Apreferred treatment process is sintering. The treatment processcomprises exposing a substrate to a source of electromagnetic radiation(EMR). In some embodiments, EMR is exposed to a substrate having a firstmaterial. In various embodiments, the EMR has a peak wavelength rangingfrom 10 to 1500 nm. In various embodiments, the EMR has a minimum energydensity of 0.1 Joule/cm². In an embodiment, the EMR has a burstfrequency of 10⁻⁴-1000 Hz or 1-1000 Hz or 10-1000 Hz. In an embodiment,the EMR has an exposure distance of no greater than 50 mm. In anembodiment, the EMR has an exposure duration no less than 0.1 ms or 1ms. In an embodiment, the EMR is applied with a capacitor voltage of noless than 100V. For example, a single pulse of EMR is applied with anexposure distance of about 10 mm and an exposure duration of 5-20 ms.For example, multiple pulses of EMR are applied at a burst frequency of100 Hz with an exposure distance of about 10 mm and an exposure durationof 5-20 ms. In some embodiments, the EMR consists of one exposure. Inother embodiment, the EMR comprises no greater than 10 exposures, or nogreater than 100 exposures, or no greater than 1000 exposures, or nogreater than 10,000 exposures.

In various embodiments, metals and ceramics are sintered almostinstantaneously (milliseconds for <<10 microns) using pulsed light. Thesintering temperature may be controlled to be in the range of 100° C. to2000° C. The sintering temperature may be tailored as a function ofdepth. In one example, the surface temperature is 1000° C. and thesub-surface is kept at 100° C., wherein the sub-surface is 100 micronsbelow the surface. In some embodiments, the material suitable for thistreatment process includes yttria-stabilized zirconia (YSZ), 8YSZ (8 mol% YSZ powder), yttrium, zirconium, gadolinia-doped ceria (GDC or CGO),samaria-doped ceria (SDC), scandia-stabilized zirconia (SSZ), lanthanumstrontium manganite (LSM), lanthanum strontium cobalt ferrite (LSCF),lanthanum strontium cobaltite (LSC), lanthanum strontium galliummagnesium oxide (LSGM), nickel, NiO, NiO-YSZ, Cu-CGO, Cu₂O, CuO, cerium,copper, silver, crofer, steel, lanthanum chromite, doped lanthanumchromite, ferritic steel, stainless steel, or combinations thereof. Thistreatment process may be suitable for any electrode or electrolytematerial previously listed herein.

This treatment process is applicable in the manufacturing process of afuel cell. In preferred embodiments, a layer in a fuel cell (i.e.,anode, cathode, electrolyte, seal, catalyst, etc) is treated usingprocesses described herein to be heated, cured, sintered, sealed,alloyed, foamed, evaporated, restructured, dried or annealed orcombinations thereof. In preferred embodiments, a portion of a layer ina fuel cell is treated using processes described herein to be heated,cured, sintered, sealed, alloyed, foamed, evaporated, restructured,dried, annealed, or combinations thereof. In preferred embodiments, acombination of layers of a fuel cell are treated using processesdescribed herein to be heated, cured, sintered, sealed, alloyed, foamed,evaporated, restructured, dried, annealed or combinations thereof,wherein the layers may be a complete layer or a partial layer.

The treatment process of this disclosure is preferably rapid, with thetreatment duration varied from microseconds to milliseconds. Thetreatment duration may be accurately controlled. The treatment processof this disclosure may produce fuel cell layers that have no cracks orhave minimal cracking. The treatment process of this disclosure controlsthe power density or energy density in the treatment volume (the volumeof an object being treated) of the material being treated. The treatmentvolume may be accurately controlled. In an embodiment, the treatmentprocess of this disclosure provides the same energy density or differentenergy densities in a treatment volume. In an embodiment, the treatmentprocess of this disclosure provides the same treatment duration ordifferent treatment durations in a treatment volume. In an embodiment,the treatment process of this disclosure provides simultaneous treatmentfor one or more treatment volumes. In an embodiment, the treatmentprocess of this disclosure provides simultaneous treatment for one ormore fuel cell layers or partial layers or combination of layers. In anembodiment, the treatment volume is varied by changing the treatmentdepth.

In an embodiment, a first portion of a treatment volume is treated byelectromagnetic radiation of a first wavelength; a second portion of thetreatment volume is treated by electromagnetic radiation of a secondwavelength. In some cases, the first wavelength is the same as thesecond wavelength. In some cases, the first wavelength is different fromthe second wavelength. In an embodiment, the first portion of atreatment volume has a different energy density from the second portionof the treatment volume. In an embodiment, the first portion of atreatment volume has a different treatment duration from the secondportion of the treatment volume.

In an embodiment, the EMR has a broad emission spectrum so that thedesired effects are achieved for a wide range of materials havingdifferent absorption characteristics. In this disclosure, absorption ofelectromagnetic radiation (EMR) refers to the process, wherein theenergy of a photon is taken up by matter, such as the electrons of anatom. Thus, the electromagnetic energy is transformed into internalenergy of the absorber, for example, thermal energy. For example, theEMR spectrum extends from the deep ultraviolet (UV) range to the nearinfrared (IR) range, with peak pulse powers at 220 nm wavelength. Thepower of such EMR is on the order of Megawatts. Such EMR sources performtasks such as breaking chemical bonds, sintering, ablating orsterilizing.

In an embodiment, the EMR has an energy density of no less than 0.1, 1,or 10 Joule/cm². In an embodiment, the EMR has a power output of no lessthan 1 watt (W), 10 W, 100 W, 1000 W. The EMR delivers power to thesubstrate of no less than 1 W, 10 W, 100 W, 1000 W. In an embodiment,such EMR exposure heats the material in the substrate. In an embodiment,the EMR has a range or a spectrum of different wavelengths. In variousembodiments, the treated substrate is at least a portion of an anode,cathode, electrolyte, catalyst, barrier layer, or interconnect of a fuelcell.

In an embodiment, the peak wavelength of the EMR is between 50 and 550nm or between 100 and 300 nm. In an embodiment, the absorption of atleast a portion of the substrate for at least one frequency of the EMRbetween 10 and 1500 nm is no less than 30% or no less than 50%. In anembodiment, the absorption of at least a portion of the substrate for atleast one frequency between 50 and 550 nm is no less than 30% or no lessthan 50%. In an embodiment, the absorption of at least a portion of thesubstrate for at least one frequency between 100 and 300 nm is no lessthan 30% or no less than 50%.

Sintering is the process of compacting and forming a solid mass ofmaterial by heat or pressure without melting it to the point ofliquefaction. In this disclosure, the substrate under EMR exposure issintered but not melted. In preferred embodiments, the EMR comprises oneor more of UV light, near ultraviolet light, near infrared light,infrared light, visible light, laser, electron beam, microwave. In anembodiment, the substrate is exposed to the EMR for no less than 1microsecond, no less than 1 millisecond. In an embodiment, the substrateis exposed to the EMR for less than 1 second at a time or less than 10seconds at a time. In an embodiment, the substrate is exposed to the EMRfor less than 1 second or less than 10 seconds. In an embodiment, thesubstrate is exposed to the EMR repeatedly, for example, more than 1time, more than 3 times, more than 10 times. In an embodiment, thesubstrate is distanced from the source of the EMR for less than 50 cm,less than 10 cm, less than 1 cm, or less than 1 mm.

In some embodiments, after EMR exposure a second material is added to orplaced on to the first material. In various cases, the second materialis the same as the first material. The second material may be exposed toEMR. In some cases, a third material may be added. The third material isexposed to EMR.

In some embodiments, the first material comprises YSZ, 8YSZ, yttrium,zirconium, GDC, SDC, LSM, LSCF, LSC, nickel, NiO or cerium or acombination thereof. The second material may comprise graphite. In someembodiments, the electrolyte, anode, or cathode comprises a secondmaterial. In some cases, the volume fraction of the second material inthe electrolyte, anode, or cathode is less than 20%, 10%, 3%, or 1%. Theabsorption rate of the second material for at least one frequency (e.g.,between 10 and 1500 nm or between 100 and 300 nm or between 50 and 550nm) is greater than 30% or greater than 50%.

In various embodiments, one or a combination of parameters may becontrolled, wherein such parameters include distance between the EMRsource and the substrate, the energy density of the EMR, the spectrum ofthe EMR, the voltage of the EMR, the duration of exposure, the burstfrequency and the number of EMR exposures. Preferably, these parametersare controlled to minimize the formation of cracks in the substrate.

In an embodiment, the EMR energy is delivered to a surface area of noless than 1 mm², or no less than 1 cm², or no less than 10 cm², or noless than 100 cm². In some cases, during EMR exposure of the firstmaterial, at least a portion of an adjacent material is heated at leastin part by conduction of heat from the first material. In variousembodiments, the layers of the fuel cell (e.g., anode, cathode,electrolyte) are thin. Preferably they are no greater than 30 microns,no greater than 10 microns, or no greater than 1 micron.

In some embodiments, the first material of the substrate is in the formof a powder, sol gel, colloidal suspension, hybrid solution or sinteredmaterial. In various embodiments, the second material may be added byvapor deposition. In preferred embodiments, the second material coatsthe first material. In preferred embodiments, the second material reactswith light, (e.g. focused light), as by a laser, and sintered orannealed with the first material.

Advantages

The preferred treatment process of this disclosure enables rapidmanufacturing of fuel cells by eliminating traditional, costly, timeconsuming, expensive sintering processes and replacing them with rapid,in situ methods that allow continuous manufacturing of the layers of afuel cell in a single machine if desired. This process also shortenssintering time from hours and days to seconds or milliseconds or evenmicroseconds.

In various embodiments, this treatment method is used in combinationwith manufacturing techniques like screen printing, tape casting,spraying, sputtering, physical vapor deposition and additivemanufacturing.

This preferred treatment method enables tailored and controlled heatingby tuning EMR characteristics (such as, wavelengths, energy density,burst frequency, and exposure duration) combined with controllingthicknesses of the layers of the substrate and heat conduction intoadjacent layers to allow each layer to sinter, anneal, or cure at eachdesired target temperature. This process enables more uniform energyapplications, decreases or eliminates cracking, which improveselectrolyte performance. The substrate treated with this preferredprocess also has less thermal stress due to more uniform heating.

Particle Size Control

Without wishing to be limited by any theory, we have unexpectedlydiscovered that the sintering process may require much less energyexpenditure and much less time than what is traditionally needed if theparticle size distribution of the particles in a material is controlledto meet certain criteria. In some cases, such particle size distributioncomprises D10 and D90, wherein 10% of the particles have a diameter nogreater than D10 and 90% of the particles have a diameter no greaterthan D90, wherein D90/D10 is in the range of from 1.5 to 100. In somecases, such particle size distribution is bimodal such that the averageparticle size in the first mode is at least 5 times the average particlesize in the second mode. In some cases, such particle size distributioncomprises D50, wherein 50% of the particles have a diameter no greaterthan D50, wherein D50 is no greater than 100 nm. The sintering processesutilize electromagnetic radiation (EMR), or plasma, or a furnace, or hotfluid, or a heating element, or combinations thereof. Preferably, thesintering processes utilize electromagnetic radiation (EMR). Forexample, without the processes as disclosed herein, an EMR source justsufficient enough to sinter a material has power capacity P. With theprocesses as disclosed herein, the material is sintered with EMR sourceshaving much less power capacity, e.g., 50% P or less, 40% P or less, 30%P or less, 20% P or less, 10% P or less, 5% P or less.

Herein disclosed is a method of sintering a material comprising mixingparticles with a liquid to form a dispersion, wherein the particles havea particle size distribution comprising D10 and D90, wherein 10% of theparticles have a diameter no greater than D10 and 90% of the particleshave a diameter no greater than D90, wherein D90/D10 is in the range offrom 1.5 to 100; depositing the dispersion on a substrate to form alayer; and treating the layer to cause at least a portion of theparticles to sinter.

In some embodiments, the particle size distribution is a numberdistribution determined by dynamic light scattering. Dynamic lightscattering (DLS) is a technique that can be used to determine the sizedistribution profile of small particles in a dispersion or suspension.In the scope of DLS, temporal fluctuations are typically analyzed bymeans of the intensity or photon auto-correlation function (also knownas photon correlation spectroscopy or quasi-elastic light scattering).In the time domain analysis, the autocorrelation function (ACF) usuallydecays starting from zero delay time, and faster dynamics due to smallerparticles lead to faster decorrelation of scattered intensity trace. Ithas been shown that the intensity ACF is the Fourier transformation ofthe power spectrum, and therefore the DLS measurements can be equallywell performed in the spectral domain.

In an embodiment, the particle size distribution is determined bytransmission electron microscopy (TEM). TEM is a microscopy technique inwhich a beam of electrons is transmitted through a specimen to form animage. In this case, the specimen is most often a suspension on a grid.An image is formed from the interaction of the electrons with the sampleas the beam is transmitted through the specimen. The image is thenmagnified and focused onto an imaging device, such as a fluorescentscreen or a sensor such as a scintillator attached to a charge-coupleddevice.

Herein disclosed is a method of sintering a material comprising mixingparticles with a liquid to form a dispersion, wherein the particles havea particle size distribution comprising D50, wherein 50% of theparticles have a diameter no greater than D50, wherein D50 is no greaterthan 100 nm; depositing the dispersion on a substrate to form a layer;and treating the layer to cause at least a portion of the particles tosinter. In various embodiments, D50 is no greater than 50 nm, or nogreater than 30 nm, or no greater than 20 nm, or no greater than 10 nm,or no greater than 5 nm. In an embodiment, the layer has a thickness ofno greater than 1 mm or no greater than 500 microns or no greater than300 microns or no greater than 100 microns or no greater than 50microns.

In some embodiments, depositing comprises material jetting, binderjetting, inkjet printing, aerosol jetting, or aerosol jet printing, vatphotopolymerization, powder bed fusion, material extrusion, directedenergy deposition, sheet lamination, ultrasonic inkjet printing, orcombinations thereof. In some embodiments, said liquid comprises waterand at least one organic solvent having a lower boiling point than waterand miscible with water. In some embodiments, said liquid compriseswater, a surfactant, a dispersant and no polymeric binder. In someembodiments, said liquid comprises one or more organic solvents and nowater. In some embodiments, the particles comprise Cu, CuO, Cu₂O, Ag,Ag₂O, Au, Au₂O, Au₂O₃, titanium, yttria-stabilized zirconia (YSZ), 8YSZ(8 mol % YSZ powder), yttrium, zirconium, gadolinia-doped ceria (GDC orCGO), samaria-doped ceria (SDC), scandia-stabilized zirconia (SSZ),lanthanum strontium manganite (LSM), lanthanum strontium cobalt ferrite(LSCS), lanthanum strontium cobaltite (LSC), lanthanum strontium galliummagnesium oxide (LSGM), nickel (Ni), NiO, NiO-YSZ, Cu-CGO, cerium,crofer, steel, lanthanum chromite, doped lanthanum chromite, ferriticsteel, stainless steel, or combinations thereof. The particles maycomprise any material previously listed herein for electrodes orelectrolyte.

In some embodiments, wherein the particles have a bi-modal particle sizedistribution such that the average particle size in the first mode is atleast 5 times the average particle size in the second mode. In someembodiments, D10 is in the range of from 5 nm to 50 nm or from 5 nm to100 nm or from 5 nm to 200 nm. In some embodiments, D90 is in the rangeof from 50 nm to 500 nm or from 50 nm to 1000 nm. In some embodiments,D90/D10 is in the range of from 2 to 100 or from 4 to 100 or from 2 to20 or from 2 to 10 or from 4 to 20 or from 4 to 10.

In some embodiments, the method comprises drying the dispersion afterdepositing. In some embodiments, drying comprises heating the dispersionbefore deposition, heating the substrate that is contact with thedispersion, or combination thereof. Drying may take place for a timeperiod in the range of 1 ms to 1 min or 1 s to 30 s or 3 s to 10 s. Insome embodiments, the dispersion may be deposited at a temperature inthe range of 40° C. to 100° C. or 50° C. to 90° C. or 60° C. to 80° C.or about 70° C.

In some embodiments, treating comprises the use of electromagneticradiation (EMR), or a furnace, or plasma, or hot fluid, or a heatingelement, or combinations thereof. In some embodiments, the EMR comprisesUV light, near ultraviolet light, near infrared light, infrared light,visible light, laser, electron beam or microwave or a combinationthereof. In an embodiment, the EMR consists of one exposure. In otherembodiments, the EMR has an exposure frequency of 10⁻⁴-1000 Hz or 1-1000Hz or 10-1000 Hz. In an embodiment, the EMR has an exposure distance ofno greater than 50 mm. In an embodiment, the EMR has an exposureduration no less than 0.1 ms or 1 ms. In an embodiment, the EMR isapplied with a capacitor voltage of no less than 100V.

EXAMPLES

The following examples are provided as part of the disclosure of variousembodiments of the present invention. As such, none of the informationprovided below is to be taken as limiting the scope of the invention.

Example 1 Making an EC Reactor Stack

Example 1 is illustrative of the preferred method of making an ECreactor stack, e.g., a fuel cell stack. The method uses an AMM model no.0012323 from Ceradrop and an EMR model no. 092309423 from Xenon Corp. Aninterconnect substrate is put down to start the print.

As a first step, an anode layer is made by the AMM. This layer isdeposited by the AMM as a slurry A, having the composition as shown inthe table below. This layer is allowed to dry by applying heat via aninfrared lamp. This anode layer is sintered by irradiating it with anelectromagnetic pulse from a xenon flash tube for 1 second.

An electrolyte layer is formed on top of the anode layer by the AMMdepositing a slurry B, having the composition shown in the table below.This layer is allowed to dry by applying heat via an infrared lamp. Thiselectrolyte layer is sintered by irradiating it with an electromagneticpulse from a xenon flash tube for 60 seconds.

Next a cathode layer is formed on top of the electrolyte layer by theAMM depositing a slurry C, having the composition shown in the tablebelow. This layer is allowed to dry by applying heat via an infraredlamp. This cathode layer is sintered by irradiating it with anelectromagnetic pulse from a xenon flash tube for ½ second.

An interconnect layer is formed on top of the cathode layer by the AMMdepositing a slurry D, having the composition shown in the table below.This layer is allowed to dry by applying heat via an infrared lamp. Thisinterconnect layer is sintered by irradiating it with an electromagneticpulse from a xenon flash tube for 30 seconds.

These steps are then repeated 60 times, with the anode layers beingformed on top of the interconnects. The result is a fuel cell stack with61 fuel cells.

Composition of Slurries Slurry Solvents Particles A 100% isopropylalcohol 10 wt % NiO-SYSZ B 100% isopropyl alcohol 10 wt % 8YSZ C 100%isopropyl alcohol 10 wt % LSCF D 100% isopropyl alcohol 10 wt %lanthanum chromite

Example 2 LSCF in Ethanol

Mix 200 ml of ethanol with 30 grams of LSCF powder in a beaker.Centrifuge the mixture and obtain an upper dispersion and a lowerdispersion. Extract and deposit the upper dispersion using a 3D printeron a substrate and form a LSCF layer. Use a xenon lamp (10 kW) toirradiate the LSCF layer at a voltage of 400V and a burst frequency of10 Hz for a total exposure duration of 1,000 ms.

Example 3 CGO in Ethanol

Mix 200 ml of ethanol with 30 grams of CGO powder in a beaker.Centrifuge the mixture and obtain an upper dispersion and a lowerdispersion. Extract and deposit the upper dispersion using a 3D printeron a substrate and form a CGO layer. Use a xenon lamp (10 kW) toirradiate the CGO layer at a voltage of 400V and a burst frequency of 10Hz for a total exposure duration of 8,000 ms.

Example 4 CGO in Water

Mix 200 ml of deionized water with 30 grams of CGO powder in a beaker.Centrifuge the mixture and obtain an upper dispersion and a lowerdispersion. Extract and deposit the upper dispersion using a 3D printeron a substrate and form a CGO layer. Use a xenon lamp (10 kW) toirradiate the CGO layer at a voltage of 400V and a burst frequency of 10Hz for a total exposure duration of 8,000 ms.

Example 5 NiO in Water

Mix 200 ml of deionized water with 30 grams of NiO powder in a beaker.Centrifuge the mixture and obtain an upper dispersion and a lowerdispersion. Extract and deposit the upper dispersion using a 3D printeron a substrate and form a NiO layer. Use a xenon lamp (10 kW) toirradiate the NiO layer at a voltage of 400V and a burst frequency of 10Hz for a total exposure duration of 15,000 ms.

Example 6 Sintering Results

FIG. 17 is a scanning electron microscopy image (side view). FIG. 17illustrates an electrolyte (YSZ) 1701 printed and sintered on anelectrode (NiO-YSZ) 1702. The scanning electron microscopy image showsthe side view of the sintered structures, which demonstrates gas-tightcontact between the electrolyte and the electrode, full densification ofthe electrolyte, and sintered and porous electrode microstructures.

Example 7 Fuel Cell Stack Configurations

A 48-Volt fuel cell stack has 69 cells with about 1000 Watts of poweroutput. The fuel cell in this stack has a dimension of about 4 cm×4 cmin length and width and about 7 cm in height. A 48-Volt fuel cell stackhas 69 cells with about 5000 Watts of power output. The fuel cell inthis stack has a dimension of about 8.5 cm×8.5 cm in length and widthand about 7 cm in height.

Example 8 Channeled Electrodes/Fluid Dispersing Components

FIG. 18 schematically illustrates an example of a half cell in an ECreactor. As shown in FIG. 18, half cell 1700 comprises interconnect1801. Interconnect 1801 comprises doped lanthanum chromite. Half cell1800 comprises anode segments 1802 that are printed on interconnect1801. The anode segments are composed of NiO-YSZ. Anode segments 1802are sintered using EMR (see Example 1). Half cell 1800 comprises fillermaterial that is deposited between anode segments 1802. The fillermaterial is polymethyl methacrylate (PMMA). Half cell 1800 includesshields 1804 that are printed on filler materials 1803 that are composedof YSZ. Additional anode material 1806 is printed to cover anodesegments 1802 and shields 1804 followed by sintering using EMR. Theadditional anode material is NiO-YSZ. Electrolyte 1805 is printed onadditional anode material 1806 and sintered using EMR. Electrolyte 1805is YSZ. A barrier layer (not shown) composed of CGO is further printedon the electrolyte and sintered using EMR. A layer of cathode (notshown) composed of LSCF is printed on the CGO barrier and sintered.Cathode segments (not shown) composed of LSCF are printed on this layerand sintered. These segments form valleys and filler PMMA is depositedto fill these valleys (not shown). Shields composed of YSZ are printedon the fillers (not shown). Doped lanthanum chromite is printed to coverthe shields and cathode segments and then sintered to form anotherinterconnect (not shown). The fillers are removed by furnace heating andchanneled electrodes are produced or fluid dispersing components areformed between electrolyte and interconnect (not shown).

It is to be understood that this disclosure describes exemplaryembodiments for implementing different features, structures, orfunctions of the invention. Exemplary embodiments of components,arrangements, and configurations are described to simplify the presentdisclosure; however, these exemplary embodiments are provided merely asexamples and are not intended to limit the scope of the invention. Theembodiments as presented herein may be combined unless otherwisespecified. Such combinations do not depart from the scope of thedisclosure.

Additionally, certain terms are used throughout the description andclaims to refer to particular components or steps. As one skilled in theart appreciates, various entities may refer to the same component orprocess step by different names, and as such, the naming convention forthe elements described herein is not intended to limit the scope of theinvention. Further, the terms and naming convention used herein are notintended to distinguish between components, features, and/or steps thatdiffer in name but not in function.

While the disclosure is susceptible to various modifications andalternative forms, specific embodiments thereof are shown by way ofexample in the drawings and description. It should be understood,however, that the drawings and detailed description are not intended tolimit the disclosure to the particular form disclosed, but on thecontrary, the intention is to cover all modifications, equivalents andalternatives falling within the spirit and scope of this disclosure.

What is claimed is:
 1. A hydrogen production system comprising: a fuelsource; a water source; and a hydrogen producer; wherein the fuel sourceand the water source are in fluid communication with the hydrogenproducer; and wherein fuel enters the hydrogen producer from the fuelsource and water enters the hydrogen producer from the water source andthe fuel and the water do not come in contact with each other in thehydrogen producer.
 2. The system of claim 1, wherein the hydrogenproducer comprises a first electrode, a second electrode, and anelectrolyte between the first and second electrodes; wherein the fuelsource is in fluid communication with the first electrode and the watersource is in fluid communication with the second electrode.
 3. Thesystem of claim 2, wherein the electrolyte comprises doped ceria orwherein the electrolyte comprises lanthanum chromite or a conductivemetal or combination thereof and a material selected from the groupconsisting of doped ceria, YSZ, LSGM, SSZ, and combinations thereof. 4.The system of claim 3, wherein the lanthanum chromite comprises undopedlanthanum chromite, strontium doped lanthanum chromite, iron dopedlanthanum chromite, lanthanum calcium chromite, or combinations thereof;and wherein the conductive metal comprises Ni, Cu, Ag, Au, orcombinations thereof.
 5. The system of claim 2, wherein the firstelectrode and the second electrode comprise Ni or NiO and a materialselected from the group consisting of YSZ, CGO, SDC, SSZ, LSGM, andcombinations thereof.
 6. The system of claim 2, wherein the firstelectrode comprises doped or undoped ceria and a material selected fromthe group consisting of Cu, CuO, Cu₂O, Ag, Ag₂O, Au, Au₂O, Au₂O₃, Pt,Pd, Ru, Rh, stainless steel, and combinations thereof; and wherein thesecond electrode comprises Ni or NiO and a material selected from thegroup consisting of YSZ, CGO, SDC, SSZ, LSGM, and combinations thereof.7. The system of claim 1, wherein the fuel from the fuel source providesheat for the hydrogen producer and the hydrogen producer has noadditional heat source.
 8. The system of claim 1 further comprising anoxidant source and a boiler, wherein the boiler is in fluidcommunication with the oxidant source, the water source, and thehydrogen producer.
 9. The system of claim 8, wherein the boiler is inthermal communication with the hydrogen producer, the fuel entering intothe hydrogen producer, the oxidant, the water, or combinations thereof.10. The system of claim 8, wherein the boiler is configured to receiveexhaust from the first electrode of the hydrogen producer and to feedsteam into the second electrode of the hydrogen producer.
 11. The systemof claim 8, wherein the fuel is partially oxidized in the hydrogenproducer and further oxidized in the boiler.
 12. The system of claim 8further comprising a steam turbine disposed between the boiler and thehydrogen producer and in fluid communication with the boiler and thehydrogen producer.
 13. The system of claim 1 further comprising a steamreformer or an autothermal reformer disposed between the fuel source andthe hydrogen producer and in fluid communication with the fuel sourceand the hydrogen producer.
 14. The system of claim 1 further comprisinga condenser configured to receive exhaust from the second electrode ofthe hydrogen producer and to recycle water to the boiler and to outputhydrogen.
 15. The system of claim 14, wherein the condenser is inthermal communication with the fuel.
 16. The system of claim 1 furthercomprising a desulfurization unit disposed between the fuel source andthe hydrogen producer and in fluid communication with the fuel sourceand the hydrogen producer.
 17. The system of claim 1, wherein thehydrogen producer is configured to have a fuel inlet temperature nogreater than 1000° C.
 18. The system of claim 1, wherein the hydrogenproducer is configured to have a fuel outlet temperature no less than600° C.
 19. The system of claim 1, wherein the hydrogen producercomprises no interconnect.
 20. The system of claim 1 in fluidcommunication with a downstream unit configured to use hydrogen producedby the hydrogen producer in one or more of process selected from thegroup consisting of: a. a Fischer-Tropsch (FT) reaction; b. a dryreforming reaction; c. a Sabatier reaction catalyzed by nickel; d. aBosch reaction; e. a reverse water gas shift reaction; f. anelectrochemical reaction to produce electricity; g. production ofammonia; h. production of fertilizer; h. electrochemical compression ofhydrogen for storage or fueling a hydrogen vehicle; or i. ahydrogenation reaction.